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  Hydrofluoric acid details

Hydrofluoric acid

Molecular Formula:HF
Molecular Weight:20.01
Use :Mainly used in the manufacture of inorganic fluorides, metallurgical analysis,
silicon compounds analysis etc.


Industrial hydrofluoric acid(Cas No.7664-39-3)

Item Name
First quality Qualifier
HF-40 HF-55 HF-40 HF-55
Hydrogen fluoride %≥ 40.0 40.0 55.0 40.0 55.0
Hydrofluosilicic acid %≤ 0.02 0.2 0.5 2.5 5.0
Fixed acid(H2SO4)  %≤ 0.02 0.05 0.08 1.0 2.0

* The HF content range from 30% to 70% upon clients’ request.

Packing: 25/230 Kg Drum;1100 Kg IBC Drum


Anhydrous hydrofluoric acid

Item Name

Hydrofluoric Content ppm ≥ 99.99 99.95 99.90
Moisture  ppm≤ 50 300 600
Fluorsoilicic Acid ppm≤ 30 100 200
Sulfur dioxide(SO2) ppm≤ 20 70 150
Non-volatile Acid(H2SO4) ppm≤ 20 50 200
As ppm ≤ 5 10

Packing: 17500/20000 Kg/ISO Tank; 680/760 Kg/Cylinder

Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water. It is a precursor to almost all fluorine compounds, including pharmaceuticals such as fluoxetine (Prozac), diverse materials such as PTFE (Teflon), and elemental fluorine itself. It is a colourless solution that is highly corrosive, capable of dissolving many materials, especially oxides. Its ability to dissolve glass has been known since the 17th century, even before Carl Wilhelm Scheele prepared it in large quantities in 1771. Because of its high reactivity toward glass and moderate reactivity toward many metals, hydrofluoric acid is usually stored in plastic containers (although PTFE is slightly permeable to it).
Hydrogen fluoride gas is an acute poison that may immediately and permanently damage lungs and the corneas of the eyes. Aqueous hydrofluoric acid is a contact-poison with the potential for deep, initially painless burns and ensuing tissue death. By interfering with body calcium metabolism, the concentrated acid may also cause systemic toxicity and eventual cardiac arrest and fatality, after contact with as little as 160 cm2 (25 square inches) of skin.
Hydrofluoric acid Acidity
Hydrofluoric acid is classified as a weak acid because of its lower dissociation constant compared to the strong acids. It ionizes in aqueous solution in a similar fashion to other common acids:
HF + H2O ? H3O+ + F?
HF is the only hydrohalic acid that is not considered a strong acid, i.e. it does not fully ionize in dilute aqueous solutions.
When the concentration of HF approaches 100%, the acidity increases dramatically because of homoassociation:
3 HF ? H2F+ + FHF?
The bifluoride (FHF?) anion is stabilized by the very strong hydrogen–fluorine hydrogen bond.
Hydrofluoric acid roduction
Hydrofluoric acid is produced by treatment of the mineral fluorite (CaF2) with concentrated sulfuric acid. When combined at 265 °C, these two substances react to produce hydrogen fluoride and calcium sulfate according to the following chemical equation:
CaF2 + H2SO4 → 2 HF + CaSO4
Although bulk fluorite is a suitable precursor and a major source of world HF production, HF is also produced as a by-product of the production of phosphoric acid, which is derived from the mineral apatite. Apatite sources typically contain a few percent of fluoroapatite, acid digestion of which releases gaseous stream consisting of sulfur dioxide (from the H2SO4), water, and HF, as well as particulates. After separation from the solids, the gases are treated with sulfuric acid and oleum to afford anhydrous HF. Owing to the corrosive nature of HF, its production is accompanied by the dissolution of silicate minerals, and, in this way, significant amounts of fluorosilicic acid are generated.
Hydrofluoric acid Uses
Hydrofluoric acid has a variety of uses in industry and research. It is used as a starting material or intermediate in industrial chemistry, mining, refining, glass finishing, silicon chip manufacturing, and in cleaning.
Hydrofluoric acid Oil refining
In a standard oil refinery process known as alkylation, isobutane is alkylated with low-molecular-weight alkenes (primarily a mixture of propylene and butylene) in the presence of the strong acid catalyst derived from hydrofluoric acid. The catalyst protonates the alkenes (propylene, butylene) to produce reactive carbocations, which alkylate isobutane. The reaction is carried out at mild temperatures (0 and 30 °C) in a two-phase reaction.
Production of organofluorine compounds
The principal use of hydrofluoric acid is in organofluorine chemistry. Many organofluorine compounds are prepared using HF as the fluorine source, including Teflon, fluoropolymers, fluorocarbons, and refrigerants such as freon.
Production of fluorides
Most high-volume inorganic fluoride compounds are prepared from hydrofluoric acid. Foremost are Na3AlF6, cryolite, and AlF3, aluminium trifluoride. A molten mixture of these solids serves as a high-temperature solvent for the production of metallic aluminium. Given concerns about fluorides in the environment, alternative technologies are being sought. Other inorganic fluorides prepared from hydrofluoric acid include sodium fluoride and uranium hexafluoride.
Hydrofluoric acid Etchant and cleaning agent
Wet etching tanks
In metalworking, hydrofluoric acid is used as a pickling agent to remove oxides and other impurities from stainless and carbon steels because of its limited ability to dissolve steel.[citation needed] It is used in the semiconductor industry as a major component of Wright Etch and buffered oxide etch, which are used to clean silicon wafers. In a similar manner it is also used to etch glass by reacting with silicon dioxide to form gaseous or water-soluble silicon fluorides. It can also be used to polish and frost glass.
SiO2 + 4 HF → SiF4(g) + 2 H2O
SiO2 + 6 HF → H2SiF6 + 2 H2O
A 5% to 9% hydrofluoric acid gel is also commonly used to etch all ceramic dental restorations to improve bonding. For similar reasons, dilute hydrofluoric acid is a component of household rust stain remover, in car washes in "wheel cleaner" compounds, in ceramic and fabric rust inhibitors, and in water spot removers.Because of its ability to dissolve iron oxides as well as silica-based contaminants, hydrofluoric acid is used in pre-commissioning boilers that produce high-pressure steam.
Hydrofluoric acid Niche applications
Because of its ability to dissolve (most) oxides and silicates, hydrofluoric acid is useful for dissolving rock samples (usually powdered) prior to analysis. In similar manner, this acid is used in acid macerations to extract organic fossils from silicate rocks. Fossiliferous rock may be immersed directly into the acid, or a cellulose nitrate film may be applied (dissolved in amyl acetate), which adheres to the organic component and allows the rock to be dissolved around it.
Diluted hydrofluoric acid (1 to 3 %wt.) is used in the petroleum industry in a mixture with other acids (HCl or organic acids) in order to stimulate the production of water, oil, and gas wells specifically where sandstone is involved.
Hydrofluoric acid is also used by some collectors of antique glass bottles to remove so-called 'sickness' from the glass, caused by acids (usually in the soil the bottle was buried in) attacking the soda content of the glass.
Offset printing companies use hydrofluoric acid to remove unwanted images from printing plates. Felt-tip markers called "deletion pens" are available to make the process safer for the worker.
Hydrofluoric acid Health and safety
A hydrofluoric acid burn of the hand
left and right hands, two views, burned index fingers
HF burns, not evident until a day after
In addition to being a highly corrosive liquid, hydrofluoric acid is also a contact poison. It should therefore be handled with extreme care, using protective equipment and safety precautions beyond those used with other mineral acids. Owing to its low acid dissociation constant, HF as a neutral lipid-soluble molecule penetrates tissue more rapidly than typical mineral acids. Because of the ability of hydrofluoric acid to penetrate tissue, poisoning can occur readily through exposure of skin or eyes, or when inhaled or swallowed. Symptoms of exposure to hydrofluoric acid may not be immediately evident, and this can provide false reassurance to victims, causing them to delay medical treatment.[9] Despite having an irritating odor, HF may reach dangerous levels without an obvious smell. HF interferes with nerve function, meaning that burns may not initially be painful. Accidental exposures can go unnoticed, delaying treatment and increasing the extent and seriousness of the injury. Symptoms of HF exposure include irritation of the eyes, skin, nose, and throat, eye and skin burns, rhinitis, bronchitis, pulmonary edema (fluid buildup in the lungs), and bone damage.
Once absorbed into blood through the skin, it reacts with blood calcium and may cause cardiac arrest. Burns with areas larger than 160 cm2 (25 square inches) have the potential to cause serious systemic toxicity from interference with blood and tissue calcium levels. In the body, hydrofluoric acid reacts with the ubiquitous biologically important ions Ca2+ and Mg2+. Formation of insoluble calcium fluoride is proposed as the etiology for both precipitous fall in serum calcium and the severe pain associated with tissue toxicity.[12] In some cases, exposures can lead to hypocalcemia. Thus, hydrofluoric acid exposure is often treated with calcium gluconate, a source of Ca2+ that sequesters the fluoride ions. HF chemical burns can be treated with a water wash and 2.5% calcium gluconate gel or special rinsing solutions.However, because it is absorbed, medical treatment is necessary; rinsing off is not enough. Intra-arterial infusions of calcium chloride have also shown great effectiveness in treating burns.
Hydrogen fluoride is generated upon combustion of many fluorine-containing compounds such as products containing Viton and polytetrafluoroethylene (Teflon) parts.[19] Hydrofluorocarbons in automatic fire suppression systems can release hydrogen fluoride at high temperatures, and this has led to deaths from acute respiratory failure in military personnel when a rocket-propelled grenade hit the fire suppression system in their vehicle. Hydrofluoric acid can be released from volcanoes, sea salt aerosol, and from welding or manufacturing processes.
Hydrofluoric acid is also a highly reactive compound and must be stored carefully to prevent dangerous reactions, though it is not flammable. It reacts with bases, acids, and oxidants and attacks glass, ceramics, concrete, some forms of plastic, rubber, and coatings. When combined with methanesulfonic acid or polymerizing cyanogens, it produces explosive gases.
While the acid’s body-dissolving effects were grossly exaggerated in the TV series, hydrofluoric acid, or HF, does indeed need to be stored and used in plastic containers as it slowly dissolves many materials, including the fibreglass many modern bathtubs are made of. HF slowly dissolves silicon dioxide – the major component of most types of glass – by forming water-soluble hexafluorosilicic acid and gaseous silicon tetrafluoride. Chemists use the acid’s ability to etch glass for removing particularly stubborn stains from laboratory glassware and it is an invaluable tool in the semiconductor industry for cleaning silicon wafers
There are certainly stronger acids than HF – with a pKa of only 3.2 it is weaker than other hydrohalide acids and a long way off superacidic fluoroantimonic acid with its extraordinary pKa of -25. The reason for HF’s meagre acidity is the strong bond between the hydrogen and the fluorine atom, resulting in only partial ionisation in dilute solutions. As is the case with other hydrogen halides, hydrofluoric acid is the aqueous solution of the colourless gas hydrogen fluoride. Commercial hydrofluoric acids contain about 50% HF, the most concentrated ones up to 75%. Interestingly, when the HF concentration approaches 100%, something curious happens: in a process called homoassociation, polyatomic ions such as HF2- and free protons form, leading to a dramatic increase in acidity.
Swedish pharmaceutical chemist Carl Scheele discovered hydrofluoric acid in 1771, when he investigated the composition of a mineral called fluorspar: Calcium fluoride. At a time when the element fluorine was unknown and all acids were thought to contain oxygen, Scheele noticed the glass-etching properties of the fumes that developed when heating fluorspar in sulfuric acid. Leading the fumes into water, he was the first to make large quantities of hydrofluoric acid. The exposure to HF – along with Scheele’s bad habit of tasting and smelling the substances he discovered – might have been one of the causes for his death at the age of just 43.
It is natural to expect hydrofluoric acid to be corrosive, but to make things worse, HF is also a strong contact poison. The acid readily penetrates the outer layers of the skin and interferes with nerve function – burns might not be immediately visible and can even remain painless, meaning accidental exposure can remain unnoticed for hours. At the body’s neutral pH, hydrofluoric acid dissociates and produces a flood of fluoride ions, which react with the abundant calcium and magnesium ions, forming insoluble salts. Alkaline metal ions are essential for the body’s proper function; their loss stops muscles working and corrodes bones. Even relatively small HF burns, about the size of the palm of your hand, can cause an array of unpleasant medical effects such as pulmonary oedema (fluid accumulation in the lungs) and life threatening cardiac arrhythmia (decreased or irregular heartbeat). Doctors treat HF poisoning with calcium gluconate injections or calcium chloride infusions to remove the fluoride ions before they devour the body’s own calcium and magnesium.
Sometimes, such as in the case of an unfortunate Australian technician, the acute fluoride poisoning can be fatal. Dissolving rock samples with hydrofluoric acid, the technician spilled a medium-sized beaker of 70% HF onto his lap – an area of about 10% of his body’s total surface. Despite immediately hosing himself and receiving treatment an hour later, the man became unconscious and died of multi organ failure two weeks later.
However, as nasty as HF might sound, a world without hydrofluoric acid would be pretty bleak. It is industry’s main source of fluorine – pharmaceuticals, refrigerants and fluoropolymers such as Teflon all rely on hydrofluoric acid.
Hydrofluoric acid poisoning
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Hydrofluoric acid is a very strong inorganic acid. This article discusses poisoning from swallowing, breathing in, or touching hydrofluoric acid.
Hydrofluoric acid poisoning can have direct effects on the heart. It can lead to irregular, and sometimes life-threatening, heartbeats.
People who come into contact with this poison are likely to have a combination of the symptoms listed.
Hydrofluoric acid is especially dangerous. The most common accidents involving hydrofluoric acid cause severe burns on the skin and hands. The burns may be extremely painful. People will have a lot of scarring and some loss of function in the area involved.
Swallowing this poison can have severe effects on many parts of the body. Extensive damage to the mouth, throat, and stomach are possible. Holes (perforations) in the esophagus and stomach may cause serious infections in the chest and abdominal cavities, which may result in death.
Hydrofluoric acid Pathophysiology
The 2 mechanisms that cause tissue damage are corrosive burn from the free hydrogen ions and chemical burn from tissue penetration of the fluoride ions. Fluoride ions penetrate and form insoluble salts with calcium and magnesium. Soluble salts also are formed with other cations but dissociate rapidly. Consequently, fluoride ions release, and further tissue destruction occurs.
Anhydrous hydrogen fluoride and hydrofluoric acid are extremely corrosive to all tissues of the body. Skin contact results in painful deep-seated burns that are slow to heal. Burns from dilute (<50%) HF solutions do not usually become apparent until several hours after exposure; more concentrated solutions and anhydrous HF cause immediate painful burns and tissue destruction. HF burns pose unique dangers distinct from other acids such as HCl and H2SO4: undissociated HF readily penetrates the skin, damaging underlying tissue; fluoride ion can then cause destruction of soft tissues and decalcification of the bones.
Hydrofluoric acid and HF vapor can cause severe burns to the eyes, which may lead to permanent damage and blindness. At 10 to 15 ppm, HF vapor is irritating to the eyes, skin, and respiratory tract. Exposure to higher concentrations can result in serious damage to the lungs, and fatal pulmonary edema may develop after a delay of several hours. Brief exposure (5 min) to 50 to 250 ppm may be fatal to humans. Ingestion of HF can produce severe injury to the mouth, throat, and gastrointestinal tract and may be fatal. Hydrofluoric acid is a clear, colorless liquid, miscible with water, with an acrid, irritating odor. It is an extremely corrosive liquid and vapor that can cause severe injury via skin and eye contact, inhalation, or ingestion.
Hydrofluoric acid has not been reported to be a human carcinogen. No acceptable animal test reports are available to define the developmental or reproductive toxicity of HF. The OSHA Permissible Exposure Limit is 3 ppm (as fluoride). Anhydrous HF has a vapor pressure of 775 mm Hg at 20℃, while Hydrofluoric acid has a vapor pressure of 14 mm Hg at 20℃ C.
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Hydrofluoric acid corrosivity
Hydrofluoric acid attacks glass, concrete, and many metals. It also attacks carbonaceous natural material such as woody materials, leather, and rubber.
Some materials resist the corrosive action of the acid, such as platinum, wax, polypropylene, polyethylene, and Teflon. In contact with metals with which it will react, hydrogen gas is liberated and the danger exists of a spark or flame resulting in an explosion. HF is used in many labs and in the glass shop on a regular basis. It should always be stored in plastic bottles. Containers of HF should be stored in secondary containers made of polyethylene in areas separate from incompatible materials. All work with hydrofluoric acid should be conducted in a fume hood to prevent exposure by inhalation. Splash goggles and Neoprene gloves as well as laboratory coats should be worn at all times to prevent eye and skin contact.
Hydrofluoric acid acid strength:
In this paper, from the view of structure to discuss the problem of HF acid strength, think system of fluorine ion in H2O in the solvent system and HF deep agent system is lead to different states and properties of hydrogen fluoride as solute and as a solvent system is the main factor of different acidity.
Compared with other hydrogen halide, HF acid has many special place, such as the polarity of the largest hydrofluoric acid is a weak acid, pure liquid hydrogen is a kind of strong acid, strong acid such as nitric acid in the liquid hydrogen fluoride becomes accept protons alkali. How to explain the hf acid is not yet well settled up a problem. The order of the strength of halogen acid as chemical materials widely used chemical thermodynamics analysis, think the hydrofluoric acid weak acid is due to H - F key button is too big and strong hydrogen bonds between HF and water (solvent) effect. As for HF concentrated solution of strong acid, general explanation for the HF has two balance in aqueous solution.
However, on the basis of thermodynamic calculation to "explain" the characteristics of HF acid has certain limitations, because it will just Δ G,Δ H and Δ S overall value to the assumptions of process (such as a bond dissociation energy, ionization energy, electron affinity, hydration energy and entropy of hydrate etc.), and the points of the process itself is experimental observations, it is difficult to calculate from the very beginning. Of strong solution thermodynamics calculation is unwise, because by concentration and calculate the ionization constants of concentrated solution acidity and based on the indicator and reflect the effect of acidity.
In conclusion, the F - ions in H2O in the solvent system and HF solvent system is lead to different states and properties of hydrogen fluoride as solute and as a solvent system is the main factor of different acidity.
The classification of high purity hydrofluoric acid:
High purity hydrofluoric acid, the formula for HF, the molecular weight is 20.01. Colorless transparent liquid, relative density 1.15 ~ 1.18, the boiling point of 112.2 ℃, smoke in the air stream, stimulating odour, highly toxic. With general metal, metal oxide and hydroxide, generate the various salts. Strong causticity, erosion and silicate glass can generate gaseous silicon tetrafluoride. Soluble in water, alcohol, soluble in other organic solvents.
High purity hydrofluoric acid as acid cleaning, etch, with nitric acid, glacial acetic acid and hydrogen peroxide and ammonium hydroxide configuration USES, mainly used in integrated circuit (IC) and very large scale integrated circuit (VLSI) chip cleaning and corrosion, the microelectronics industry is one of the key basic chemical material in the production process, also can be used as analytical reagent preparation of high purity and containing fluorine chemicals. At present, in China is basically used as etching agent and cleaning agent in the microelectronics industry, less dosage of other aspects.
SEMI International (Semiconductor Equipment and Materials International) standardization organization according to the actual development of high-purity reagent in the worldwide scale, classified according to the varieties, each species incorporated into a guidance standard, including multiple level for different process technology. The domestic some high purity reagent production enterprises have their own standards, among them, BV series standards are common, the standard is divided into seven levels.
At present, due to the different standards for the microelectronics manufacturing enterprise of high purity hydrofluoric acid, it can be divided into four levels: (1) low-grade products, used in > 1.2 mu mIC technology of production; (2) the medium product, suitable for 0.8 ~ 1.2 mu mIC technology of production; (3) in high-grade products, suitable for 0.2 ~ 0.6 mu mIC technology of production; (4) a high grade product, suitable for 0.09 ~ 0.2 microns and < 0.09 mu m IC technology.
High purity hydrofluoric acid preparation method and process:
Common purification technology for the preparation of high purity hydrofluoric acid at home and abroad are: distillation, distillation, and boiling distillation, gas absorption technology, such as the purification techniques have different characteristics, different. Some purification techniques such as the boiling distillation technology can only be used for the preparation of the product quantity is little, and some purification techniques such as gas absorption technology can be used in mass production. Therefore, when choosing technology route should be depending on the actual situation. In addition, because the hydrofluoric acid has strong corrosion resistance, the use of distillation process of the distillation equipment used in general need platinum, gold, silver and other precious metals or teflon etc. The capability of corrosion resistance of materials to manufacturing.
High purity hydrogen production unit process arrangement to give priority to with vertical flow, anhydrous hydrofluoric acid raw materials and high pure water in the upper, the purification of hydrofluoric acid in the middle, filtration, packaging and stored in the ground floor. Because the raw material (anhydrous hydrofluoric acid and high pure water) and intermediate can rely on gravity flow from top to bottom, avoid using pump to save energy, reduce the production cost. Here is a kind of distillation, absorption of combining the production technology of producing high purity hydrofluoric acid.
The anhydrous hydrofluoric acid after chemical pretreatment through feeding pump into the high slot, again through flow control into the rectification column, refined after hydrogen fluoride gas is obtained by distillation operation, and turn it into the absorption tower, rectifying column residual liquid made industrial emissions and hydrofluoric acid on a regular basis. In the absorption tower, by adding after measurement, the high pure water, make the distillation of high purity hydrogen fluoride gas formation after hydrofluoric acid, and can be used to control methods such as spray density, gas liquid ratio make further purification, high purity hydrofluoric acid crude product. Then after super clean filtering process, make the product mix and get further filtering, guarantee the particles of qualified products. Finally in purifying indoor packing for final product - high purity hydrofluoric acid.
Impurity arsenic is the need to control an important impurities in high purity hydrofluoric acid, arsenic in hydrofluoric acid raw materials generally exists in the form of three valence, and AsF3 differ with the boiling point of hydrofluoric acid is not big, so only by distillation for the separation effect is not ideal. For arsenic removal of impurities, can be in the process of distillation, adding suitable amount of strong oxidizer (such as potassium permanganate, etc.) will be three valence state of arsenic oxide, make it in the deposit on the tower in the process of distillation kettle and be removed.
Facilities of hydrofluoric acid:
1, Analysis, control and product testing:
With the continuous development of the microelectronics industry production technology of high-purity hydrofluoric acid requirements are also getting higher and higher - required to control the particle size getting smaller and smaller, the requirements of metal and non-metallic impurities getting low (impurity Trace Trace  is even ppm or even ppb / ppt / ppc level), which requires manufacturers must have the ability to analyze control and product testing to match. However, these analyzes control and product testing equipment is expensive, highly specialized technical operation and high requirements, general management and small and medium enterprises is difficult to bear, so that the final products are generally identified or directly to users through the authorized testing center test use and identification, in order to obtain customer acceptance.
Preparation of high purity hydrofluoric acid the test instruments are as follows: (1) high-frequency inductively coupled plasma mass spectrometry (ICP-MS); (2) by inductively coupled plasma atomic emission analyzer (IeP-AES); (3) Atomic Absorption spectrophotometer; (4) the oxygen atom flameless atomic absorption analyzer; (5) ion chromatographic analyzer; (6) laser light scattering particle counter liquid; (7) meter and impurity analysis system; (8) to the original force between microscope; (9) optical microscope particle counter; (10) scanning electron microscope; (11) and the optical film thickness measuring surface profiling instrument; (12) surface tension tester; (13) in air dust particle analyzer; (14 ) water resistivity meter.
2, High purity water--essential raw material to produce hydrofluoric acid
High purity water is an indispensable raw material for the production of high purity hydrofluoric acid, but also the packaging container of cleaning agent, which will directly affect the purity of the product quality high-purity hydrofluoric acid. The main control targets are high water resistivity and solid particles, other auxiliary indicators total oxidizable carbon (TOC), bacteria, dissolved silica, ion concentration. Currently, high purity water production technology is more mature, more common is the first by an ion exchange column and micro filter to give ordinary water, then using reverse osmosis, electrodialysis and other membrane technology for further processing, with the final sterilization and ultrafiltration can obtain high purity water.
3,The package of high-purity hydrofluoric acid:
High-purity hydrofluoric acid is highly corrosive, because the higher quality requirements in the IC production industry, so the packaging technology requirements more stringent. First, the containers must have a corrosion resistance, and secondly to prevent the products appear secondary pollution. Currently the most widely used material is a high density polyethylene (HDPE), tetrafluoroethylene and perfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE).
4, Environment of hydrofluoric acid factory
Factory workshop, analysis room, warehouses and other closed environments, to achieve a certain degree of cleanliness, typically 10000 (hydrofluoric acid with high purity product grade and improve); to maintain a certain temperature (22.2 ± 2.5 ℃, the specific operation site control 22.2 ± 0.11 ℃), about humidity (40%, not less than 30%, not more than 50%).
Here we make a detailed introduce of the current market situation and current production situation for hydrofluoric acid in China, look back the history evolution for hydrofluoric acid technology development in China. Summarize and compare the current technology process for hydrofluoric acid, give a relative introduction about current research process for sulphate acid-fluorite other processes.
Put emphasis on introducing several process technology harvests for using Fluosilicate acid to hydrofluoric acid, consider that there has a great strategic significance for hydrofluoric acid industry and technology developing in China when fluorine resource of fluosilicate acid be utilized efficient. The late 1950s, the need for national defense industry, began developing hydrofluoric acid production technology. Since the relative abundance of fluorite resources, coupled with hydrofluoric acid applications ranging from military defense to expanding refrigeration and air conditioning, aerospace, automotive, textile, chemical, pharmaceutical industry and so on, increasing demand; and because many foreign businessmen have come to China Sourcing hydrofluoric acid, resulting in a significant increase in the two major domestic and international market demand for hydrofluoric acid, promote the vigorous development of the production of hydrofluoric acid.
Hydrofluoric acid is the foundation of modern fluorine chemical industry, is making element fluorine, a variety of fluorine refrigerant, fluorine and new materials, inorganic fluoride salts, various organic fluorides of basic raw materials. So explore efficient energy consumption, environmental protection and sustainable development of hydrogen fluoride production technology has a very important significance and far-reaching impact on the fluorine chemical industry.
First aid measures of hydrofluoric acid burns:
1, Before the operation of hydrofluoric acid, please carefully check for leaks latex gloves, wash their hands after each operation.
2, Contaminated by hydrofluoric acid, do not panic, timely reporting and department heads immediately with plenty of cold running water for 15-30 minutes, then the affected area is immersed in a saturated solution of magnesium sulfate; easy to immerse immersed saturated magnesium sulfate with a clean dressing after the solution was wet, cold packs placed on top of the best. Every 10 minutes for a dressing.
3, Continuous immersion or cold compresses to the affected area four hours after the magnesium sulfate solution blisters or swelling, should be kept cold state to the professional hospital for disposal.
4, The affected area can not be damaged soaked in magnesium sulfate solution, go to the hospital after the rinse water for disposal.
Hydrofluoric acid reactor:
Hydrofluoric acid, hydrofluoric acid production line reactor is the most important equipment, due to the bulky, heavy weight, the production line is the most difficult to install equipment. Hydrofluoric acid reactor is the largest volume of the whole plant equipment, the total length of the reactor 30 m, a diameter of 3 m, the cylinder on the total weight 140.3 t, with the last round cylinder weight 10.3 t, is the construction process of the project most important and difficult one.
Anhydrous hydrogen fluoride production, crude hydrogen fluoride gas generated by the reactor has a high temperature, highly toxic, highly corrosive properties, and a certain amount of entrained dust. These features give the selection pipeline, piping, and etc. made high design requirements.
Anhydrous hydrofluoric acid production process hazardous factors:
Anhydrous hydrofluoric acid is an extremely corrosive acid. Its physical characteristics are wide liquid temperature range, high conductivity, polar, boiling point, freezing point, low viscosity and surface tension, chemical properties of fluorocarbon chains having active and strong chemical activity, with almost all types of organic or inorganic compounds bind. China is emerging as the work of fluorinated fine chemical industry, anhydrous hydrofluoric acid can be widely used in industrial, civil and national defense industries. E.g. fluorine plastic widely used, fluorine rubber, fluorine refrigerants, fluorine-containing coating, fluorine-containing surfactant and a fluorine-containing pharmaceutical products.
Hydrofluoric acid: Pumps and compressors category:
Chemicals used in many types of pumps and compressors, the present production process commonly used in conventional centrifugal pump, vortex pump, liquid hydrocarbon pumps, gear pumps, metering pumps, etc., as well as corrosion-resistant diaphragm pump, pump anti-corrosion lining, shielding pumps, pump and other alloys. There used to transport sulfuric acid, made larger flow pump fuming sulfuric acid, anhydrous hydrogen fluoride, etc., have for the recovery of by-product hydrochloric acid, fluorosilicic acid, hydrofluoric acid and neutralized with caustic circulation pump, but also a small amount of resistance for injection polymerization inhibitor triethylamine and special metering pumps polymer additives and the like. Most of these materials are highly corrosive, and some have some toxicity, should be attention during operation and maintenance. Their common precautions such as: outlet valve is not open or opening is too small, so that the resistance increases, causing the outlet pressure exceeds a predetermined generating material in the joint or leak at the valve. Pump rotating parts of the seal is also very easy problem areas should be checked regularly to ensure they are in good sealed state.
Organic fluorine used in the production of raw materials, intermediate products, finished products, many are "dangerous chemicals in China" (2002 Edition), GB 13690-1992 "commonly used classification of dangerous chemicals and signs", GB 12268-1990 "dangerous goods items watch "and" highly toxic chemicals directory "(2002 edition) and other standards identified as toxic and inflammable and explosive materials or corrosive materials. In the production, storage, transportation, use and other processes, often due to accidental leaks, improper operation, faulty contact and the risk of accidents caused. Especially in the production process, the greater the possibility of danger. Of anhydrous hydrogen fluoride, and chlorine-containing perfluorinated tetrafluoroethylene isobutylene distillation residue, which is widely distributed in both the production process equipment, and stored in cylinders. Since the cylinder was pressurized state, during storage and transportation within and outside the plant vulnerable to leaks. Hydrogen fluoride and chlorine gas moisture or water will generate highly corrosive inorganic acids; organic fluorine containing olefin residue in the water is also very easy to generate an organic acid, which is more big possibility of damage to equipment and piping. Other typical dangerous chemicals have been: sulfuric acid, fuming sulfuric acid, fluorosilicic acid, hydrofluoric acid, water, sodium hydroxide (caustic soda), chloroform (chloroform), hydrochloric acid, antimony trichloride, antimony pentachloride , tetrafluoroethylene, hexafluoropropylene, triethylamine, persulfate or organic peroxide.
Fluorine chemical industry, almost all production units are inseparable from the basic raw material of anhydrous hydrogen fluoride, anhydrous hydrogen fluoride and the production of the main raw material to concentrated sulfuric acid and oleum are highly corrosive mineral acids, more due to corrosion and leaks the most likely to cause injury is a pipe weld, flange interface, valves, pumps, seals, and also more likely to occur when splashing or ejection during sampling and inspection, must pay attention to protect your face and exposed skin. The production process of the finished product containing unreacted sulfuric acid, hydrofluoric acid products, as well as a mixture of fluorine acid and the like, which is highly corrosive mixture of inorganic acids in the operation also need to pay attention to not touch the body.
A byproduct of fluorosilicic acid and hydrofluoric acid are corrosive acids, especially in the open valves and pumps, the system pressure is too high and do not cause leakage. When by-product packaging, often using artificial filling, the other handling, weighing, also commonly used by hand, more prone to accidents.
Under normal production conditions, the entire process system of harmful substances (besides hydrogen fluoride, also have sulfuric acid, fuming sulfuric acid and so on) is not going to leak out, but when any abnormal operation caused by pressure fluctuations when it material leakage may occur. In addition, the maintenance system of the prior inadequately treated, remaining in the equipment and piping dead toxic gases may escape. Storage container of anhydrous hydrogen fluoride or anhydrous hydrogen fluoride there since the pipeline run, run, drip, leak, leak may occur. Another type of valve is fitted with an extreme case of anhydrous hydrogen fluoride vessel and on the pipe, parts suddenly due to corrosion damage, or accidental impact damage, a large number of hydrogen fluoride to escape, causing serious poisoning.
The typical case of danger of hydrofluoric acid:
In 1991 a factory in Hubei anhydrous hydrogen fluoride finished tank, due to the observation level sight glass suddenly broken, a lot of liquid hydrofluoric acid tank discharge, resulting in one dead and one seriously injured.
1991 anhydrous hydrogen fluoride large tank factory in Guangdong Huiyang, liquid outlet pipe valve failure and maintenance, the operator inadvertently forgot to cut off the pipeline, the inner tube remains liquid hydrofluoric acid, but not required to wear protective supplies, hydrofluoric acid also caused the discharge, the same result one person was killed and one seriously injured.
Anhydrous hydrogen storage tank in a specific factory replacement level timing, although according to regulations prior to open the vent valve venting pressure relief valve may be due to the opening was not big enough, the discharge time is not long, and pressure not drained. Unchecked operator test, then disassemble the level gauge, causing the liquid discharge, resulting in two deaths.
Overview on electronic grade hydrofluoric acid:
By the end of 2011, the national electronic-grade hydrofluoric acid production capacity of about 80,000 tons, but production is less than 50,000 tons. Electronic grade hydrofluoric acid has four levels (PPT level, UP-S grade, UP level, EL grade), packaging with bottles of high density polyethylene material, tons of barrels and tankers. Products are mainly used in integrated circuits, solar photovoltaic, liquid crystal displays, LED semiconductor industry.
Currently used for producing an electronic grade hydrofluoric acid purification technology at home and abroad have distillation, distillation, sub-boiling distillation, vacuum distillation, gas absorption technology, these purification technologies have their own characteristics. Such as sub-boiling distillation technique can only be used to prepare a small amount of product, gas absorption technology for large-scale production. Further, since the highly corrosive hydrofluoric acid, the use of corrosion at high temperature distillation process will be more serious, so the distillation apparatus used is generally required platinum, gold, silver and other precious metals such as polytetrafluoroethylene or corrosion resistance capacity than strong material to make. Closely related to the electronic-grade hydrofluoric acid production plant design and process layout, the vertical arrangement of the flow of raw materials (anhydrous hydrofluoric acid and high purity water) and the intermediate product can flow by gravity from top to bottom, in the middle of the preparation of high purity hydrofluoric acid, the product filtration, bottling and storage at the bottom. This arrangement can reduce the pump delivery, save energy, reduce production costs, while avoiding secondary pollution pump products.
Dangers of Hydrofluoric Acid
Hydrofluoric Acid is one of the most dangerous acids known. It needs to be treated differently than even strong acids like Sulfuric and Hydrochloric.
Hydrofluoric Acid is an acid like no other. It is so potent that contact with it may not even be noticed until long after serious damage has been done. Even very strong acids, and mixtures of acids, like Aqua Forte and Aqua Regia, do not have the power to cause death and injury in the way that Hydrofluoric Acid can.
Why is Hydrofluoric Acid so Dangerous?
Hydrofluoric Acid has two mechanisms that cause tissue damage:Corrosive Burns from free hydrogen ions Chemical Burns from tissue penetration of the fluoride
ion.Fluoride ions penetrate and form insoluble salts with calcium and magnesium.
Soluble salts are also formed with other cations but dissociate rapidly. Consequently, fluoride ions release, and further tissue destruction occurs.
Hydrofluoric Acid vs Other Acids
Hydrofluoric acid (HF) differs from other acids because the fluoride ion readily penetrates the skin, causing destruction of deep tissue layers,including bone. Pain associated with exposure to solutions of HF (1-50%) may be delayed for 1-24 hours. If Hydrofluoric Acid is not rapidly neutralized and the fluoride ion bound, tissue destruction may continue for days and result in limb loss or death.
Hydrofluoric Acid is similar to other acids in that the initial extent of a burn depends on the concentration,the temperature, and the duration of contact with the acid.
Hydrofluoric Acid Mortality/Morbidity
Local effects include tissue destruction and necrosis. Burns may involve underlying bone.Systemic fluoride ion poisoning, from severe burns is associated with hypocalcemia (low
calcium levels), hyperkalemia (high potassium levels), hypomagnesemia (low magnesium levels) and sudden death.
Deaths have been reported from concentrated acid burns involving as little as 2.5% Body Surface Area (BSA).
Storing Hydrofluoric Acid
Store in a cool, dry place away from incompatible materials. HF reacts with many materials therefore avoid contact with glass,concrete, metals, water, other acids, oxidizers,
reducers, alkalis, combustibles, organics and  ceramics.
Store in containers made of polyethylene or fluorocarbon plastic, lead, or platinum. Place storage bottles in polyethylene secondary containment trays.
Never store HF in glass containers.
Ensure all areas where HF is used are equipped with proper spill response equipment. Small spills can be neutralized by covering with magnesium sulfate (dry) and absorbed with spill control pads or other absorbent materials. Add sodium bicarbonate or magnesium oxide to an absorbent and place in a plastic container for disposal. Wash the spill site with a sodium bicarbonate solution. Or use a commercial spill kit. Call EHS (4-5084) to dispose of spill clean-up materials. All spill clean-up materials must be placed in a plastic container.
3M's Universal Sorbent is recommended, as it does not react with HF. Organic spill kits that contain Floor-Dri, kitty litter, vermiculite or sand should not be used because HF reacts with silica to produce silicon tetrafluoride, a toxic gas.
If the spill is large, in a confined space, or in an area where there is not adequate ventilation, or if the acid is concentrated evacuate the room and immediately report the spill to EHS (4-5084) or after hours call 911.
Fire and Explosion Hazard
Hydrogen fluoride is non-combustible, but may create irritating and corrosive fumes of fluorides when heated or in combination with steam or water. Since hydrogen fluoride does not burn,use an extinguishing agent suitable for surrounding fire. Use water to absorb fumes and keep containers cool. Heat released when water or steam combines with hydrogen fluoride or hydrofluoric acid could be hazardous. For fires involving hydrofluoric acid, apply water in flooding quantities. Hydrofluoric acid and various metals may form hydrogen (extremely flammable gas) creating a fire hazard.
Symptoms of Hydrofluoric Acid Burns
The Hydrogen Fluoride molecule is so mobile that it may easily pass through the skin.Because Fluorine has an extremely high affinity for Calcium, bones will be attacked,
and this may result in hypocalcaemia. There may be no pain immediately after the burn,leading the injured person to believe that they are not in danger.
Symptoms of Exposure
CONCENTRATIONS LESS THAN 20% -Erythema (skin redness) and pain may be delayed up to 24 hours, often not reported until tissue damage is extreme. In one study,7% HF produced symptoms in 1 to several hours, 12% Hydrofluoric Acid in less than one hour, and 14.5% Hydrofluoric Acid immediately.
CONCENTRATIONS 20 TO 50% - Erythema and pain may be delayed from 1 to 8 hours,and is often not reported until tissue damage is extreme.
CONCENTRATIONS GREATER THAN 50% -Produces immediate burning, erythema, and tissue damage.
Decontamination and First Aid
Immediately remove all exposed clothing taking necessary precautions to prevent self-exposure(wear gloves) while washing all exposed areas with copious amounts of water.
Application of 2.5 to 33% calcium gluconate or carbonate gel or slurry, either placed into a surgical glove into which the affected extremity is then placed, or rubbed into the burn, is recommended.
Use calcium gluconate for dermal treatment only.DO NOT USE CALCIUM CHLORIDE – Calcium chloride is irritating to the tissues and may cause injury.
Hydrofluoric Acid EXPOSURE KIT
Before beginning work involving Hydrofluoric Acid an exposure kit must be available and located in the laboratory area. The exposure kit must contain the following items:
Container of calcium gluconate gel This gel must be inspected before each use of HF or at least monthly to ensure the gel has not been removed or has not reached the expiration date. If a tube of the gel has been opened, a new container must be purchased and the old container discarded.No work with HF can be done with an expired tube of calcium gluconate gel.
Hydrofluoric Acid EXPOSURE KIT cont.
2 pairs of Neoprene or Nitrile (22mil) gloves 1 heavy-duty polyethylene bag to be used for items contaminated by HF 1 HF Contaminated Waste Label Copy of CHP and MSDS to take to the emergency room Calcium Carbonate (antacid tablets)
First Aid for Inhalation Exposure
If a large volume of Hydrofluoric Acid gas is inhaled:Immediately remove the victim to clean air. Call 911 Inform 911 operator of Hydrofluoric Acid exposure and instruct them to notify hospital of person in transport Inhalation of Hydrofluoric Acid fumes may cause swelling in the respiratory tract up to 24 hours after exposure. Persons who have inhaled Hydrofluoric Acid vapors may need prophylactic oxygen treatment and must be seen by a physician as soon as possible
Hydrofluoric Acid Accidents
1981 –At the Sullivan Park Research Facility of Corning, Inc., an Hydrofluoric Acid tank leaked. A cleanup crew went in without proper respirators and 2 workers died.
1994 –A lab tech in Western Australia died from burns sustained when he accidentally spilled concentrated (70%) HF on himself.
1996 –A NYC sanitation worker died of toxic fumes released when Hydrofluoric Acid blew up in the back of his truck.
Study of Fatal HF Poisonings
From 1984 to 1994 9 deaths were investigated from 8 industrial incidents Unsafe work practices were implicated in each incident Calcium chloride or gluconate was noted to
have been administered to 5 of the 9 victims
Handling Hydrofluoric Acid
Familiarize yourself with the hazards specific to HF before handling.Hydrofluoric Acid should never be handled by anyone who has not been trained to use it.
Always handle HF in:A properly functioning fume hood An area equipped with a Safety Shower/Eye Wash Calcium Gluconate should be available for skin treatment.
Recommended Personal Protective Equipment:Goggles Face shield (plastic)
Gloves: Thin disposable gloves (such as 4, 6, or 8 mil blue Nitrile glove) used in laboratory operations provide a contact barrier only and should be disposed of
immediately when contamination is suspected. Thicker (10-20 mil) PVC or neoprene gloves provide good resistance to HF but do not provide the necessary dexterity for most lab procedures. Thinner PVC or poly (“food” handling) gloves can provide some resistance to HF, but should also be changed immediately at the first sign of contamination. Disposable gloves should never be worn without double gloving because of the potential for pinholes and exposure. A combination of double gloves, Nitrile and poly, can be used to provide greater protection from a broader range of materials.Acid resistant apron Long pants, sleeves, and closed toe shoes (always required when working with corrosives)
Working With Hydrofluoric Acid Safely
Never use Hydrofluoric Acid when working alone or after hours. Always ensure that knowledgeable laboratory personnel have been alerted and at least one is in the general
All lab personnel, not just those who will be using Hydrofluoric Acid, should be informed of the dangers of this chemical and the emergency procedures necessary in case of
an accident. A sign should be posted to alert people that work with Hydrofluoric Acid is in progress.
All persons who will be using Hydrofluoric Acid must be made aware of its properties and trained in proper procedures for use and disposal.
Laboratories which keep or use Hydrofluoric Acid gas or concentrated solutions (>1% Hydrofluoric Acid) should have emergency procedures on hand as well as an MSDS.
Laboratories which keep or use Hydrofluoric Acid gas or concentrated solutions (>1% Hydrofluoric Acid) must have an operational safety shower and eye wash in their laboratory.
Before beginning any procedure involving Hydrofluoric Acid, make sure the access to the emergency shower and eyewash is unobstructed.
Undergraduate students should never be given the task of mixing Hydrofluoric Acid solutions. Only experienced persons familiar with its properties should handle the concentrated acid.Clean up all spills promptly. Purchase HF in limited quantities. Keep as little on hand as possible (3 month or less supply).
When working with Hydrofluoric Acid or concentrated HF solutions (> 1%):Work in a fume hood with the sash as low as possible. Wear goggles and a face shield. Wear a long-sleeved, buttoned lab coat, pants or long skirt, and closed-toe shoes. Wear Neoprene or Nitrile (22mil) gloves or other Hydrofluoric Acid resistant gloves (Hydrofluoric Acid burns around the fingernails are extremely painful, difficult to treat, and may require surgical removal of the nail). A chemically resistant apron is also recommended.
Double gloving is highly recommended. Make sure your gloves have no pin-holes.Any exposure to Hydrofluoric Acid must be medically evaluated.
Do not leave tongs, stirrers, etc., which have been contaminated with HF in fume hoods where other people may pick them up or otherwise come into contact with them.
Any unattended containers must be labelled.If it is not feasible to do this, and containers must be left in the laboratory fume hood unattended by the HF user, place a placard or sign in the fume hood indicating the HF hazard.When the work has been completed and personal protective equipment has been removed, wash hands thoroughly with soap and water.
Properly dispose of contaminated disposable gloves, aprons, etc in a plastic container and close it so it is spill proof. All waste containers must be labeled with a hazardous waste label with the chemical name written out.
The principle investigator shall supply a CHP for the processes involving HF to affected employees and verify that they understand it.
Employees should understand the health and physical hazards of HF. The ability of HF to inflict damage without initial pain should be emphasized.
Solutions with concentrations > 50% may release hazardous concentrations of HF vapor under conditions of poor ventilation and require respirator use. If
employees wish to use respirators when using HF, such respirators shall ONLY be obtained after proper training in respirator use. The principle investigator shall ensure
that only employees who have received respirator training and have received appropriate medical exams by an Occupational Health Physician are allowed to wear respirators. Persons wearing respirators must also be fit tested for their respirator annually.
Summary of Hydrofluoric Acid
Hydrofluoric Acid is an extremely dangerous chemical, and can cause death from a skin exposure of less than 3% of body area.Special training, preparation, Personal Protective Equipment,and handling precautions are needed at all times.
This training is not a substitute for medical advice, Risk Assessments, Chemical Safety Data Sheets, or any other professional service that needs to be used before dealing with
Hydrofluoric Acid.
If you are exposed to hydrofluoric acid seek medical attention immediately, even if you do not feel pain. It may take up to 24 hrs to feel the pain from <20% HF exposure.
In order to warn and protect others from the hazard of HF, a warning sign indicating the use of HF should be posted.
Torrance residents, politicians call for ban on hydrofluoric acid at refinery
Hydrofluoric acid is used in the refining of petroleum to create gasoline, but it can pose a danger to the public when not handled properly.
“Hydrofluoric acid is extremely dangerous. It is so dangerous that if released into the air, it forms a vapor cloud that travels around with the wind and kills people who come in contact with it,” Congressman Ted Lieu of Torrance said.
The refinery uses a modified version of hydrofluoric acid, but critics say the formula isn’t much safer than the original.
Muratsuchi, who is running for another term in the Assembly, laid out a six-point plan to overhaul the safety guidelines at the refinery. In addition to an outright ban on the use of modified hydrofluoric acid, the points included:
installation of real-time air quality monitors, along with the sharing of real-time data with residents
installation of a more effective community alarm system
an update to the community disaster preparedness plan specifically addressing the threat of modified hydrofluoric acid
Hydrofluoric Acid Market Research Report Now Available at Research Corridor
Research Corridor has published a new research study titled “Hydrofluoric Acid Market – Growth, Share, Opportunities, Competitive Analysis and Forecast, 2015 – 2022”. The Hydrofluoric Acid market report studies current as well as future aspects of the Hydrofluoric Acid Market based upon factors such as market dynamics, key ongoing trends and segmentation analysis. Apart from the above elements, the Hydrofluoric Acid Market research report provides a 360-degree view of the Hydrofluoric Acid industry with geographic segmentation, statistical forecast and the competitive landscape.
Geographically, the Hydrofluoric Acid Market report comprises dedicated sections centering on the regional market revenue and trends. The Hydrofluoric Acid market has been segmented on the basis of geographic regions into North America, Europe, Asia Pacific and Rest of the World (RoW). The RoW segment consists Latin America and the Middle East & Africa. The Hydrofluoric Acid market has been extensively analyzed on the basis of various regional factors such as demographics, gross domestic product (GDP), inflation rate, acceptance and others. Hydrofluoric Acid Market estimates have also been provided for the historical years 2013 & 2014 along with forecast for the period from 2015 – 2022.
The research report also provides a comprehensive understanding of Hydrofluoric Acid market positioning of the major players wherein key strategies adopted by leading players has been discussed. The Hydrofluoric Acid industry report concludes with the Company Profiles section which includes information on major developments, strategic moves and financials of the key players operating in Hydrofluoric Acid market.
Key Takeaways:
Market Dynamics in the Hydrofluoric Acid Market
Key Ongoing Regional Trends
Hydrofluoric Acid Market Estimates for Years 2013 – 2022
Hydrofluoric Acid Market Positioning of Key Players
Key Strategies Adopted by the Leading Players
Attractive Investment Proposition
Hydrofluoric Acid Market Inclination Insights
worldwide hydrofluoric acid market size, share, trend, growth, analysis and forecast report 2016 – acute market reports
this report studies hydrofluoric acid in global market, especially in north america, europe, china, japan, southeast asia and india, focuses on top manufacturers in global market, with capacity, production, price, revenue and market share for each manufacturer, covering
chevron phillips chemical company llc.
royal dutch shell (shell)
honeywell international inc.
dow chemicals
clariant ag
lyondellbasell industries n.v
johnson matthey
chevron phillips chemical company llc.
ineos group ag
market segment by regions, this report splits global into several key regions, with production, consumption, revenue, market share and growth rate of hydrofluoric acid in these regions, from 2011 to 2021 (forecast), like
north america
southeast asia
split by product type, with production, revenue, price, market share and growth rate of each type, can be divided into
type i
type ii
type iii
split by application, this report focuses on consumption, market share and growth rate of hydrofluoric acid in each application, can be divided into
1 hydrofluoric acid market overview
1.1 product overview and scope of hydrofluoric acid
1.2 hydrofluoric acid segment by type
1.2.1 global production market share of hydrofluoric acid by type in 2015
1.2.2 type i
1.2.3 type ii
1.2.4 type iii
1.3 hydrofluoric acid segment by application
1.3.1 hydrofluoric acid consumption market share by application in 2015
1.3.2 environmental
1.3.3 refinery
1.3.4 polymer
1.4 hydrofluoric acid market by region
1.4.1 north america status and prospect (2011-2021)
1.4.2 europe status and prospect (2011-2021)
1.4.3 china status and prospect (2011-2021)
1.4.4 japan status and prospect (2011-2021)
1.4.5 southeast asia status and prospect (2011-2021)
1.4.6 india status and prospect (2011-2021)
1.5 global market size (value) of hydrofluoric acid (2011-2021)
2 global hydrofluoric acid market competition by manufacturers
2.1 global hydrofluoric acid capacity, production and share by manufacturers (2015 and 2016)
2.2 global hydrofluoric acid revenue and share by manufacturers (2015 and 2016)
2.3 global hydrofluoric acid average price by manufacturers (2015 and 2016)
2.4 manufacturers hydrofluoric acid manufacturing base distribution, sales area and product type
2.5 hydrofluoric acid market competitive situation and trends
2.5.1 hydrofluoric acid market concentration rate
2.5.2 hydrofluoric acid market share of top 3 and top 5 manufacturers
2.5.3 mergers & acquisitions, expansion
3 global hydrofluoric acid capacity, production, revenue (value) by region (2011-2016)
3.1 global hydrofluoric acid capacity and market share by region (2011-2016)
3.2 global hydrofluoric acid production and market share by region (2011-2016)
3.3 global hydrofluoric acid revenue (value) and market share by region (2011-2016)
3.4 global hydrofluoric acid capacity, production, revenue, price and gross margin (2011-2016)
3.5 north america hydrofluoric acid capacity, production, revenue, price and gross margin (2011-2016)
3.6 europe hydrofluoric acid capacity, production, revenue, price and gross margin (2011-2016)
3.7 china hydrofluoric acid capacity, production, revenue, price and gross margin (2011-2016)
3.8 japan hydrofluoric acid capacity, production, revenue, price and gross margin (2011-2016)
3.9 southeast asia hydrofluoric acid capacity, production, revenue, price and gross margin (2011-2016)
3.10 india hydrofluoric acid capacity, production, revenue, price and gross margin (2011-2016)
4 global hydrofluoric acid supply (production), consumption, export, import by regions (2011-2016)
4.1 global hydrofluoric acid consumption by regions (2011-2016)
4.2 north america hydrofluoric acid production, consumption, export, import by regions (2011-2016)
4.3 europe hydrofluoric acid production, consumption, export, import by regions (2011-2016)
4.4 china hydrofluoric acid production, consumption, export, import by regions (2011-2016)
4.5 japan hydrofluoric acid production, consumption, export, import by regions (2011-2016)
4.6 southeast asia hydrofluoric acid production, consumption, export, import by regions (2011-2016)
4.7 india hydrofluoric acid production, consumption, export, import by regions (2011-2016)
5 global hydrofluoric acid production, revenue (value), price trend by type
5.1 global hydrofluoric acid production and market share by type (2011-2016)
5.2 global hydrofluoric acid revenue and market share by type (2011-2016)
5.3 global hydrofluoric acid price by type (2011-2016)
5.4 global hydrofluoric acid production growth by type (2011-2016)
6 global hydrofluoric acid market analysis by application
6.1 global hydrofluoric acid consumption and market share by application (2011-2016)
6.2 global hydrofluoric acid consumption growth rate by application (2011-2016)
6.3 market drivers and opportunities
6.3.1 potential applications
6.3.2 emerging markets/countries
7 global hydrofluoric acid manufacturers profiles/analysis
7.1 basf
7.1.1 company basic information, manufacturing base and its competitors
7.1.2 hydrofluoric acid product type, application and specification type i type ii
7.1.3 basf hydrofluoric acid capacity, production, revenue, price and gross margin (2015 and 2016)
7.1.4 main business/business overview
7.2 chevron phillips chemical company llc.
7.2.1 company basic information, manufacturing base and its competitors
7.2.2 hydrofluoric acid product type, application and specification type i type ii
7.2.3 chevron phillips chemical company llc. hydrofluoric acid capacity, production, revenue, price and gross margin (2015 and 2016)
7.2.4 main business/business overview
7.3 royal dutch shell (shell)
us doe awards depleted uranium contract
under the contract, the atkins-led joint venture will operate the facilities to convert the doe's inventory of about 765,000 tonnes of duf6, a produced alongside enriched uranium at the doe's former gaseous diffusion uranium enrichment operations at the sites, to depleted uranium oxide for possible future re-use, storage or disposal. aqueous hydrofluoric acid, which can be re-used in industrial processes, is a co-product of the conversion of duf6.
mid-america conversion services was selected from five proposals received by doe in response to its contract solicitation. the joint venture will also be responsible for selling the aqueous hydrofluoric acid produced in the operation as well as for reusing or transporting and disposing of end-products and wastes, and providing surveillance and maintenance services for the duf6 cylinder inventory.
doe selects fluor jv to operate the depleted uf6-conversion facilities
the project includes the operation of duf6 conversion facilities for the purpose of processing doe’s inventory of stored duf6, a co-product of the uranium enrichment process. the facilities convert duf6 to depleted uranium oxide for possible future reuse, storage or disposal. a co-product of the conversion process is hydrofluoric acid, which can be reused in industrial processes.
mid-america conversion services, llc, is a fully integrated team, which will operate the two duf6 conversion facilities to continue the conversion of the doe’s inventory of approximately 765,000 metric tons of depleted uranium hexafluoride to depleted uranium oxide. the team of leading nuclear industry experts will also broker the sale of the aqueous hydrofluoric acid product and provide surveillance and maintenance services for the duf6 cylinder inventory.
Learn details of the global hydrofluoric acid sales market forecast to 2021 covering investment feasibility, company profiles, competitive landscape, and industry chain structure
Global Hydrofluoric Acid Sales Industry 2016 Market Research Report provide the details about Industry Overview and analysis about Manufacturing Cost Structure, Revenue, Gross Margin, Consumption Value and Sale Price, Major Manufacturers, Distributors, Industry Chain Structure, New Project SWOT Analysis with Development Trends and Forecasts 2021.
The Global Hydrofluoric Acid Sales Industry 2016 Market Research Report is a professional and in-depth study on the current state of the Hydrofluoric Acid Sales industry. With around 150 tables and figures this report provides key statistics on the state of the industry and is a valuable source of guidance and direction for companies and individuals interested in the market.
Development policies and plans are discussed as well as manufacturing processes and Bill of Materials cost structures are also analyzed. This report also states import/export consumption, supply and demand Figures, cost, price, revenue and gross margins.
Companies like Basf, Chevron Phillips Chemical Company, Royal Dutch Shell, Honeywell International, Albemarle, Exxonmobil, Dow Chemicals, Dupont, Sinopec, Axens, Clariant, Lyondellbasell Industries, Johnson Matthey, Chevron Phillips Chemical Company, Ineos Group and more are profiled in the terms of product picture, specification, capacity, production, price, cost, gross, revenue, and contact information.
Global Hydrofluoric Acid Sales Market report provides a basic overview of the industry including definitions, classifications, applications and industry chain structure. Upstream raw materials and equipment and downstream demand analysis is also carried out.
The Hydrofluoric Acid Sales industry development trends and marketing channels are analyzed. Finally the feasibility of new investment projects are assessed and overall research conclusions offered.
Table of Contents:
1 Industry Overview of Hydrofluoric Acid Sales
2 Manufacturing Cost Structure Analysis of Hydrofluoric Acid Sales
3 Technical Data and Manufacturing Plants Analysis of Hydrofluoric Acid Sales
4 Capacity, Production and Revenue Analysis of Hydrofluoric Acid Sales by Regions, Types and Manufacturers
5 Price, Cost, Gross and Gross Margin Analysis of Hydrofluoric Acid Sales by Regions, Types and Manufacturers
6 Consumption Volume, Consumption Value and Sale Price Analysis of Hydrofluoric Acid Sales by Regions, Types and Applications
7 Supply, Import, Export and Consumption Analysis of Hydrofluoric Acid Sales
8 Major Manufacturers Analysis of Hydrofluoric Acid Sales
9 Marketing Trader or Distributor Analysis of Hydrofluoric Acid Sales
10 Industry Chain Analysis of Hydrofluoric Acid Sales
11 Development Trend of Analysis of Hydrofluoric Acid Sales
12 New Project Investment Feasibility Analysis of Hydrofluoric Acid Sales
13 Conclusion of the Global Hydrofluoric Acid Sales Industry 2016 Market Research Report
What are the use of hydrofluoric acid in life
Hydrofluoric acid is a typical chemical. Many chemical reagents are corrosive, and different chemicals are to be held in containers of different textures. Some chemical corrosion of glass is very strong, such as hydrofluoric acid, hydrofluoric acid and when glass contacts, quickly put the glass corroded, therefore, can not use glass containers for hydrofluoric acid, must be placed in a container or plastic made of lead in.
Hydrofluoric acid is an aqueous solution of hydrogen fluoride (HF). Hydrogen fluoride is a colorless gas with a pungent odor. It is quite easy to change into liquid. Hydrogen fluoride is liquefied at 19.5 degrees centigrade. Hydrogen fluoride is soluble in water and is an unlimited solution. Hydrogen fluoride smokes in moist air because of the formation of fine droplets combined with water vapor in the air.
This is the hydrofluoric acid corrosion of glass, the adverse effects, according to the normal mentality, people think is to try to prevent hydrofluoric acid and glass contact, but glass craftsmen using reverse thinking but let the positive effect of hydrofluoric acid corrosion glass has this characteristic.
What is the use of industrial grade hydrofluoric acid?
Industrial grade hydrofluoric acid industrial grade hydrofluoric acid is the hydrofluoric acid gas dissolved in water into aqueous solution, from the outside not clear what color, but once a smoke is a strong pungent odor, is a commonly used industrial raw materials.
Industrial grade hydrofluoric acid can dissolve the oxide, used to purification of aluminum and uranium and plays an important role, can also be used to etch glass, the semiconductor industry uses it to remove the silicon oxide surface, it can be used in isobutane and butane refinery alkylation catalyst, oxygen containing stainless steel surface to remove the impurities of "acid" the process will use hydrofluoric acid. Hydrofluoric acid is also used in a variety of fluorinated organic compounds, such as Freon refrigerants.
Because of the strong acid corrosion of industrial hydrofluoric acid, we must pay attention to safety when operating, such as wearing gas masks and rubber gloves. We can not use glass bottles to hold them, nor do we use brushes when cleaning. We must put safety at an earlier position.
The use and characteristics of hydrofluoric acid
With the development of the science and technology, more and more local water use hydrofluoric acid, it can solve the problems in our life, it can be used for carving glass, or is used to control fermentation, wall cleaning of the building, with the production of aqueous hydrofluoric acid aluminum fluoride and cryolite is essential additives in aluminum smelting industry.
Using hydrofluoric acid production of sodium fluosilicate acid is used in construction of concrete and acid resistant cement coagulant, hydrofluoric acid cleaning agent or the iron and steel, electronics industry. In addition, fluoride salts produced by hydrofluoric acid are widely used in food protection, special metal smelting, leather and textile processing, specimen preservation, and nuclear industry, etc.. Also used in the production of easy to pack ammonium hydrogen fluoride, sodium fluosilicate, etc.; removal of stainless steel surface oxygen impurities in the "acid leaching" process will also use hydrofluoric acid. Because of its ability to dissolve oxides, hydrofluoric acid plays an important role in the purification of aluminium and uranium; in petroleum refineries, it can be used as a catalyst for alkylation of isobutane and butane. Because of the relatively strong combining ability between hydrogen atoms and fluorine atoms, hydrofluoric acid can not be completely dissociated in water.
But there is water, hydrofluoric acid in the process of delivery, also need to pay attention to the delivery of the problem, not because of improper transportation lead to water hydrofluoric acid pollution of the environment, endanger the health of the body, the man-made direct personal injury. Excellent, these work is also a great guarantee for enterprises to achieve.
What should be paid attention to when there is water hydrofluoric acid in use?
With the development of science and technology, there are more and more widely used in aqueous hydrofluoric acid, it can solve the problems in our life, it can be used for carving glass, or is used to control the fermentation, wall cleaning of buildings, water production of aluminum fluoride and hydrofluoric acid cryolite is refined
Indispensable auxiliary agent for aluminum industry. Using hydrofluoric acid production of sodium fluosilicate acid is used in construction of concrete and acid resistant cement coagulant, hydrofluoric acid cleaning agent or the iron and steel, electronics industry. In addition, fluoride salts produced by hydrofluoric acid are widely used in food protection
Kinds of metal smelting, leather and textile processing, specimen preservation, and nuclear industry, etc.. Also used in the production of easy to pack ammonium hydrogen fluoride, sodium fluosilicate, etc.; removal of stainless steel surface oxygen impurities in the "acid leaching" process will also use hydrofluoric acid. Dissolved oxides due to hydrofluoric acid
Its ability to play an important role in the purification of aluminium and uranium; in petroleum refineries, it can be used as a catalyst for alkylation of isobutane and butane. Because of the relatively strong combining ability between hydrogen atoms and fluorine atoms, hydrofluoric acid can not be completely dissociated in water.
But there is water, hydrofluoric acid in use, but also need to pay attention to the problem of delivery, not because of improper transport during use, lead to water hydrofluoric acid pollution of the environment, endanger the health of the body, causing personal injury.
Be careful when using hydrofluoric acid
Hydrofluoric acid is a corrosive, toxic, inorganic acid, so in use, be sure to be careful, otherwise it is very easy to cause harm to human health.
1, in use, once accidentally spilled on the skin, at first the skin will appear flushing phenomenon, and will feel the skin is very dry. Over a period of time the skin will become very pale, the skin has necrosis, then the skin will become purple black or black. as
When the fruit burns badly, or when it is treated improperly, it results in a deep ulcer of the skin, which can severely damage the periosteum and bone of the human body.
2, because this kind of inorganic acid easily volatile, so when in use must wear goggles and masks, because inorganic acid volatile enters the eyes, can cause corneal perforation, a serious cause of blindness. If inhaled, it can cause pneumonia and support
Bronchitis and other diseases.
3, in addition, it also makes people's olfactory degradation, so that the teeth appear acid corrosion disease, but also cause skeletal fluorosis.
Therefore, we must be careful when using hydrofluoric acid and proceed in accordance with the regulations concerning the operation of inorganic acids
General requirements for hydrofluoric acid production operations
Hydrofluoric acid products are toxic, highly corrosive, and highly irritating and can cause burns in humans. Although this product does not burn, it can react with many metals to produce hydrogen gas and cause explosion. When a H foaming agent is encountered, it immediately burns. Highly corrosive. therefore
In production, we must pay attention to the steps of operation.
1, operators must undergo special training, strictly abide by the operating procedures, proficiency in operating skills, with emergency handling knowledge. The operator must stand on the wind;
2, strictly sealed, to prevent leakage, providing sufficient local ventilation and ventilation or outdoor settings, providing safe shower and eye cleaning equipment. A hydrogen fluoride toxic gas detecting alarm device shall be set up on the spot. Equipped with more than two heavy-duty protective clothing. Wear rubber acid resistance
Alkaline clothing, wearing rubber, acid and alkali gloves, workplace concentration exceeded the standard, operators should wear a self - suction filter type gas mask. Isolation, mechanization and automation should be adopted. Avoid mist.
3, the tank pressure containers and equipment should be set to the safety valve, pressure gauge, level gauge, thermometer, and should be equipped with a safety device with pressure, temperature and liquid level remote recording and alarm function, set the rectifier and press, power supply, pipeline pressure, ventilation facilities or
Interlocking device of absorption device. Emergency cut-off device shall be installed in key storage tank.
4. Avoid contact with oxidants, acids, alkalis.
5 safety warning signs shall be set up in the production and storage areas.
6. Do gas tightness check before starting.
7, equipment and pipe flanges with PTFE gasket seal.
8, regularly replace the valve, reactor, mixing and other corrosion prone equipment and pipe fittings. Such as: often open the valve three months to replace, often open the valve for one month, six months to replace.
The formation mechanism of titania nanotube arrays in hydrofluoric acid electrolyte
Self-organized and highly ordered titania nanotube arrays (TNAs) were prepared through electrochemical anodic oxidization on a titanium foil in 0.5% hydrofluoric acid (HF) electrolyte. The current density and morphology images during the formation process of TNAs were studied. Results show that the formation of TNAs includes the following processes. Initially, dense oxide of titania was rapidly formed on the titanium surface, followed by small pore formation. The adjacent small pores were then integrated and become larger pores. At the same time, small tubes were transformed. These small tubes were further integrated into larger tubes until the primary tube formation. Finally, the tubular structure was gradually optimized and eventually developed into the highly ordered TNAs. A model was proposed to explain the formation mechanism of TNAs fabricated on a titanium foil in HF acid electrolyte.
Chemical Properties of Oxidized Silicon Carbide Surfaces upon Etching in Hydrofluoric Acid
Hydrogen termination of oxidized silicon in hydrofluoric acid results from an etching process that is now well understood and accepted. This surface has become a standard for studies of surface science and an important component in silicon device processing for microelectronics, energy, and sensor applications. The present work shows that HF etching of oxidized silicon carbide (SiC) leads to a very different surface termination, whether the surface is carbon or silicon terminated. Specifically, the silicon carbide surfaces are hydrophilic with hydroxyl termination, resulting from the inability of HF to remove the last oxygen layer at the oxide/SiC interface. The final surface chemistry and stability critically depend on the crystal face and surface stoichiometry. These surface properties affect the ability to chemically functionalize the surface and therefore impact how SiC can be used for biomedical applications.
Characterization and adsorption properties of diatomaceous earth modified by hydrofluoric acid etching
This work was a study of the chemical modification of diatomaceous earth (DE) using hydrofluoric acid (HF) solution. Under the experimental conditions investigated, it was found that HF under controlled conditions significantly etched inward into the interior of the existing pore structure in the clay mineral due to its high content of silica, leaving a framework possessing a larger BET surface area (ca. 10 m 2 65g 611 ) in comparison with that (ca. 4 m 2 65g 611 ) of its precursor (i.e., DE). Further, the results indicated that the HF concentration is a more determining factor in creating more open pores than other process parameters (temperature, holding time, and solid/liquid ratio). This observation was also in close agreement with the examinations by the silicon analysis, scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The adsorption kinetics and the adsorption isotherm of methylene blue onto the resulting clay adsorbent can be well described by a pseudo-second-order reaction model and the Freundlich model, respectively.
Fatal systemic fluorosis due to hydrofluoric acid burns
A patient with a 70% hydrofluoric acid burn developed systemic dissemination of fluoride ion from a 9% to 10% body surface area exposure on the lower extremities. Severe hypocalcemia and intractable ventricular arrhythmias resulted. This case is the second documented occurrence of hypocalcemia from hydrofluoric acid burns. It is the first case to document myocardial injury and systemic fluorosis from a skin burn.
Adsorption of Elements from Hydrofluoric Acid by Anion Exchange
Elution characteristics for some 50 elements in a hydrofluoric acid medium were studied with a strongly basic anion exchange resin. Estimates of distribution coefficients in 1 to 24M acid were obtained by spectrographic analysis of column effluent solutions. Possible analytical separations are suggested from the adsorption data observed for elements in this medium.
Possible hazardous effects of hydrofluoric acid and recommendations for treatment approach: a review
Abstract Hydrofluoric acid (HF) is commonly used for conditioning the glass ceramics either prior to cementation or for intraoral repair in prosthetic and restorative dentistry. The present study offers a review of chemical properties of HF used, highlight the possible hazardous effects of this agent, and to recommend the treatment approach for potential risks. Available published information documented in PubMed, Medline, and Picarta literature databases was reviewed. Additional information was derived from scientific reports, medical and chemical textbooks, handbooks, product information, manufacturers' instructions, Internet web sites of the HF manufacturers. No report was found on the incidence of the hazardous effects of HF in dentistry. Reports from other fields presented incidences of acute and chronic symptoms in exposure to HF. While acute symptoms include skin or nail burns, chronic ones involve systemic toxicity, eye injuries, inhalation and ingestion-related symptoms that can be even fatal. HF can be harmful and particularly aggressive to soft tissues, but symptoms may not be apparent immediately after exposure. The hazardous effects are not based on the pH value, but on the toxicity of HF. Potential hazards of HF known from other applications than dentistry should be considered also in dental applications. Especially the clinicians, who often deal with adhesive cementation or repair of glass ceramics, should take necessary precautions for possible hazards of HF.
The synthesis of SAPO-34 and CoSAPO-34 from a triethylamine?hydrofluoric acid?water system
The synthesis of the highly selective methanol-to-olefin catalysts SAPO-34 and CoSAPO-34, using a unique combination of triethylamine templating agent and fluoride ion mineralizer, is reported. The control of both the Si/Al/P ratio and template content of the reaction gel mixture allows the formation of the other SAPO-based zeolitic systems. The fluoride ion mineralizer causes a reduction in nucleation time and an increase in crystallinity of SAPO-34. The structure-directing effects of the triethylamine template are discussed and shown to predominate through steric influences, rather than electronic effects. This was confirmed by quantitative thermogravimetric analysis and molecular-graphics techniques.
Fatality due to acute systemic fluoride poisoning following a hydrofluoric acid skin burn.
Reports indicate that death due to hydrofluoric acid exposure is usually the result of inhalation of vapor causing pulmonary edema and fluoride poisoning. Absorption via the skin route of fluoride ion sufficient to cause serious systemic problems and even death has rarely been reported. A fatality resulting from a severe facial burn, which produced acute systemic fluoride poisoning with profound hypocalcemia and hypomagnesemia, is presented. The importance of proper personal protective equipment as well as the immediate initiation of first aid and appropriate medical measures, including the monitoring and replacement of serum calcium and magnesium, are emphasized.
Comparison of acidulated phosphate fluoride gel and hydrofluoric acid etchants for porcelain-composite repair
Abstract Hydrofluoric acid etches porcelain to produce a porous surface visible under scanning electron microscopy when compared to an acidulated phosphate fluoride gel. Some investigators have suggested the greater porosity of the hydrofluoric acid etch produces a greater composite-to-porcelain bond. This investigation tested that assumption with two common fluoride etchants. The etched surfaces were first viewed under scanning electron microscopy to ensure that a characteristic etch was achieved. Both etchants yielded bond strengths that produced cohesive failure of all samples. This suggested that the intraoral use of hydrofluoric acid is no more effective than the less dangerous acidulated phosphate fluoride gel.
Nucleation behavior in electroless displacement deposition of metals on silicon from hydrofluoric acid solutions
We investigate the nucleation behavior in the electroless displacement deposition of metal particles (Pt, Rh, Pd, Cu, Ag, and Au) onto n-Si wafers from a metal-salt solution containing HF. The particle density of metals varies widely from 10 6 (Pt) to 10 11 (Au) cm 鈭2 , depending on the kind of metal. Deposited metals can be classified into two types of nucleation behavior. One consists of the platinum group elements, including Pt, Rh, and Pd, which display lower particle densities than elements of the other group and depend on the type of pretreatment of the n-Si wafer, and thus the surface conditions of Si. The second group consists of the copper group elements, including Cu, Ag, and Au, which display higher particle density than the first group and are independent of pretreatment. The size of deposited particles decreases from hundreds nm to tens nm as the particle density increases. Moreover, the displacement deposition of the Pt and Ag particles onto n-Si are in progressive and instantaneous nucleation modes, respectively.
The effect of epoxy coating containing emeraldine base and hydrofluoric acid doped polyaniline on the corrosion protection of AZ91D magnesium alloy
Corrosion protection of epoxy coatings containing emeraldine base polyaniline (PANI) or hydrofluoric acid doped PANI on AZ91D magnesium alloy were studied by EIS and Pull-Off Adhesion Test. The results indicated that the addition of emeraldine base PANI or hydrofluoric acid doped PANI could improve the corrosion resistance of epoxy coating. The epoxy coating containing hydrofluoric acid doped PANI had the best performance of the corrosion protection among three systems under investigation. The corrosion product film was analyzed by XPS indicating that PANI changed the chemical structure of the corrosion film. The protective mechanism imparted by PANI was discussed.
Determination of Cu and Mn in seawater by graphite furnace atomic absorption spectrometry with the use of hydrofluoric acid as a chemical modifier
The addition of hydrogen fluoride to a seawater sample in a graphite tube atomizer makes possible the removal of the major matrix components in an optimized pre-heating step, thus a near interference free determination of copper and manganese trace metals is achieved. The optimization studies were supported by a priori calculation of limit of detection (LOD) data. For optimized conditions, the experimentally determined LOD values (3σ, n =20) were 0.11 and 0.03 μg l 611 for Cu and Mn, respectively, for 20 μl applied seawater volume. With the use of calibration with standard addition, determined concentrations of Cu and Mn in CASS-2 seawater and in SLEW-1 estuarine water were in good agreement with certified values at the 95% confidence level ( n =10).
Description Concentration Special Grade
Hydrofluoric acid, 48 wt. % in H2O, ≥99.99% trace metals basis, 48 wt. % in H2O
Hydrofluoric acid, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., ≥48%,
ACS reagent, reag. ISO, reag. Ph. Eur.
Hydrofluoric acid, puriss. p.a., reag. ISO, reag. Ph. Eur., ≥40%,
reag. ISO, reag. Ph. Eur.
Hydrofluoric acid, ACS reagent, 48%,
ACS reagent
Hydrofluoric acid, technical, 40-45%,

Hydrofluoric acid, semiconductor grade MOS PURANAL? (Honeywell 17928), 49.5-50.5%,
semiconductor grade MOS PURANAL? (Honeywell 17928)
Hydrofluoric acid, for ultratrace analysis, 47-51% (T),

Hydrofluoric acid-induced hypocalcemia
Abstract Among patients exposed to hydrofluoric acid the potentially lethal effect of calcium depletion induced by binding with fluoride ion has not been well reported. Three patients exposed to hydrofluoric acid had acute fluoride poisoning with serum calcium levels equal to or below 4.1 mgm/dl. Treatment included administration of large amounts of calcium, both intravenously and by subsechar injection, to replenish the biologically active calcium and to bind fluoride. This report describes successful treatment of two survivors, apparently the first two, of severe hypocalcemia caused by hydrofluoric acid.
Acute hydrofluoric acid exposure
Significant local and systemic toxicity may occur from hydrofluoric acid by all routes of exposure. Prompt decontamination by removal from the source and copious irrigation of eyes and skin are essential to reduce morbidity and mortality. Ingestion of small amounts of HF can lead to rapid systemic poisoning and death. Calcium gluconate therapy has become the preferred method of detoxifying the fluoride ion, although its efficacy is based mainly on anecdotal reports and poorly controlled clinical studies. Therefore, more basic research is needed to elucidate the pathophysiology of local toxicity and the best therapeutic modalities to limit injury. All significant exposures should be evaluated by health care personnel familiar with the potential toxicity of this compound.
Hydrofluoric acid: a review of toxicity
Hydrofluoric acid is a toxic substance used widely in both industrial and domestic settings. It can cause severe burns, as well as systemic toxicity. Death has been reported from as little as 2.5% body surface area (BSA) burn involving concentrated acid. Topical and parenteral calcium salts have proven effective therapy for both dermal and systemic manifestations. All emergency physicians should be aware of the unique complications and treatment of these injuries.
Detection of gas trace of hydrofluoric acid using microcantilever
Microcantilevers have been used as a gas sensor in order to detect Hydrofluoric acid (HF) in the concentration range of 0.26–1302ppm. Silicon derived elements (Si 3 N 4 , SiO x ) were chosen to serve as chemical sensitive layer. Cantilever deflection and frequency shift were analyzed and compared as a function of the flow rate and the concentration of the HF molecules. The stoichiometry and roughness of the sensitive layer were found to be of major importance. Results show that the most appropriate signal at the lowest concentration (<1002ppm) is the cantilever deflection that is particularly sensitive to the change in surface stress induced by the lateral attack of SiO x surface by HF. The frequency shift that is mainly governed by the loss in cantilever mass can be used at higher concentration.
Hydrofluoric acid pre-treatment for improving 13C CPMAS NMR spectral quality of forest soils in south-east Queensland, Australia
Hydrofluoric acid (HF) was used to pre-treat forest soils of south-east Queensland for assessing the effectiveness of iron (Fe) removal, carbon (C) composition using C-13 cross-polarisation (CP) with magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) before and after the HF pre-treatment, and the improvement of C-13 CPMAS NMR spectra. Soil samples were collected from 4 experimental sites of different soil types, harvest residue management or prescribed burning, and tree species. More than 86% of Fe was in all soil types removed by the HF treatment. The C-13 NMR spectral quality was improved with increased resolution, especially in the alkyl C and O-alkyl C regions, and reduced NMR run-time (1-5 h per sample compared with >20 h per sample without the pre-treatment). The C composition appeared to alter slightly after the pre-treatment, but this might be largely due to improved spectrometer conditions and increased resolution leading to more accurate NMR spectral integration. Organic C recovery after HF pre-treatment varied with soil types and forest management, and soluble soil organic matter (SOM) could be lost during the pre-treatment. The Fourier Transform-Infrared (FT-IR) spectra of HF extracts indicated the preferential removal of carboxylic C groups during the pre-treatment, but this could also be due to adsorbed water on the mineral matter. The NMR spectra revealed some changes in C composition and quality due to residue management and decomposition. Overall, the HF treatment was a useful pre-treatment for obtaining semi-quantitative C-13 CPMAS NMR spectra of subtropical Australian forest soils.
Hydrofluoric acid pre-treatment for improving 13C CPMAS NMR spectra quality of forest soils in southeast Queensland, Australia.
Fluorine‐containing species on the hydrofluoric acid etched silicon single‐crystal surface
The chemical structure and property of fluorine‐containing species on the hydrofluoric acid (HF) etched Si surface was examined by use of x‐ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The fluorine content on the surface was found to increase with increase of HF concentration. A silicon surface etched by 50% HF has fluorine of 2.6×1014atoms/cm2as Si–F. Most of the Si–F bondings are rapidly hydrolyzed to Si–OH by rinsing the wafer in water. Thus prepared Si–OH groups are found to be useful as active sites for chemical modification of the bare silicon single‐crystal surface. The Si–F was observed not to influence the oxidation rate of HF etched silicon surface.
Mechanism of Copper Deposition on Silicon from Dilute Hydrofluoric Acid Solution
Abstract Metal deposition on silicon from HF‐based solutions is initiated by electrochemical reduction of metal ions, a process which is driven by the difference between the electron quasi Fermi energy in the silicon, E Fn, and the redox energy level of the ions in solution, . Mechanisms for metal ion reduction are elucidated by aligning the silicon bands with the redox levels of ions in solution. For copper, the reduction reaction occurs by capture of conduction band electrons, a process which requires nucleation of nanometer‐sized precipitates on the silicon surface. As the concentration of electrons at the surface, n s, is increased (e.g., by n‐type doping, illumination, or cathodic biasing), the nucleation rate of precipitates, N, increases steeply. N is further dependent on the activity of the metal ion in solution and the amount of surface charge at the Si/HF interface. The growth rate, v, of copper nuclei is determined by the surface concentration of holes, p s, and is increased by illumination and p‐type doping. The predicted effects on N and v of illumination level, doping level, and substrate bias were verified by immersion tests on Czochralski wafers in 1:100 HF. Total reflection x‐ray fluorescence was used to measure copper coverage; atomic force microscopy and surface‐sensitive minority carrier lifetime measurements were used to determine the areal density of copper precipitates. Application of these findings to reduce copper deposition from HF in industrial wafer cleaning practice are discussed.
Soluble surfactant additives for ammonium fluoride/hydrofluoric acid oxide etchant solutions
Silicon trioxide etching solutions with soluble surfact additives are provided. The improved silicon dioxide etchants are produced by adding soluble perfluornated surfactant additives to standard oxide etchants in the manufacture of integrated circuits. These surfactant additives are unique because they remain dissolved in the oxide etchant (ammonium fluoride/hydrofluoric acid mixture) even after 0.2 micron filtration. In addition, the filtered solutions retain their surface active properties and are low in metallic ion impurities. The surfactant additives provide etchant solutions with lower surface tensions, which improves substrate wetting and yields better etchant performance. The surfactant does not leave residues or adversely affect etchant profiles.
Method of electrolessly depositing metals on a silicon substrate by immersing the substrate in hydrofluoric acid containing a buffered metal salt solution
A thin layer of Class 1B, IIB, IIIA, IVB, VB, VIB, VIIB or VIIIB metal is deposited on silicon or a silicon-based compound by immersion in a buffered metallic salt bath containing a hydrofluoric acid etchant followed by an electroless plating bath to build up the metal thickness. This process can also be used to pattern deposited metal on silicon or a silicon-based compound. An additional use of this process is to form metal silicides out of the deposited metal.
Hydrofluoric acid etcher and cascade rinser
An apparatus used to HF gas etch a plurality of integrated circuit wafers within an etch chamber, followed by a de-ionized water cascade rinse in the chamber. On completion of the rinse and removal of the wafer carriers, the apparatus, housing, and supply conduits are purged with an inert gas to prepare the apparatus for a next batch of wafer carriers. The apparatus includes process-control means for automatically controlling each step of the process
Hydrofluoric acid burns of the hand: mechanism of injury and treatment
Hydrofluoric acid is one of the strongest inorganic acids and is used extensively in industry and research. It differs from other acids in that the fluoride ion readily penetrates the skin, causing destruction of deep tissue layers and even bone. Authors have previously described numerous topical treatments. This report describes one method of treatment emphasizing immediate skin cleansing and the application of calcium gluconate gel, which is followed by calcium gluconate subcutaneous injections when necessary. An accurate occupational history and physical examination are important aspects of patient assessment. Prompt treatment resulted in relief of pain and a satisfactory clinical result in all cases. A significant delay in treatment was responsible for permanent impairment in 2 of 14 patients.
Topical Treatments for Hydrofluoric Acid Burns: A Blind Controlled Experimental Study
Background: Calcium gluconate gel, applied after initial rinsing with water, has a documented effect as first aid treatment for hydrofluoric acid burns. Hexafluorine庐 is a novel liquid compound developed especially for emergency decontamination of hydrofluoric acid eye and skin exposures. However, scientific documentation of the effect of Hexafluorine is insufficient. This study was undertaken to compare Hexafluorine with water rinsing plus topical calcium and with water rinsing alone. Methods: Thirty-five Sprague-Dawley rats were anesthetized and their backs shaved. Four filter papers 10 mm in diameter were soaked in 50% hydrofluoric acid and applied on the shaved area of each rat for 3 minutes. Thirty seconds later, the acid-exposed skin areas were rinsed with 500 mL Hexafluorine for 3 minutes (group H, n = 10), 500 mL water for 3 minutes (group W, n = 10) or 500mL water for 3 minutes followed by a single application of 2.5% calcium gluconate gel (group Ca, n = 10), or received no treatment (controls, n = 5). The animals were closely observed for 5 days. Daily at 4 P.M. each of the four burns on every rat was rated on a modified Draize scale graded from 0 to 5 (0 = no visible injury, I = diffuse erythema, 2 = distinct erythema, 3 = distinct erythema plus wounds or discolored spots, 4 = distinct erythema plus wounds or discolored areas covering >50% of the burn, 5 = a necrotic wound covering the whole burn). The mean of the four scores was then calculated for each animal and day. The rating procedure was performed by one laboratory assistant who was unaware of the treatment given. Kruskal-Wallis analysis was used to evaluate possible differences between treatment groups on each of the 5 days. If the p-value obtained was <0.05, correction for multiple comparisons was made. Results: The mean severity score in group H was significantly higher than that in group Ca on days 2 and 3. Moreover, Hexafluorine showed a consistent trend towards a worse outcome, both in comparison to water plus topical calcium and to water rinsing alone. Conclusion: Based on these observations it is concluded that water rinsing followed by topical calcium should remain the standard first aid treatment for skin exposure to hydrofluoric acid.
Fabrication of biconical tapered optical fibers using hydrofluoric acid
An easy to implement procedure for etching silica fibers in biconical form useful in sensing applications is described. A simple etching reactor was developed to obtain reproducible tapers of desired diameter and length. An approach for on-line monitoring of etching using a commonly used fluorometer is demonstrated. A mathematical model describing the light power transmission is proposed, and is validated using experimental data. The data and the model indicate that the diameter of the silica fiber decreases linearly with time with hydrofluoric acid (HF, 49.5% w/w) used as etchant at room temperature. The observed etching rate was 0.0023±0.00019 s 611 , which was repeatable using the procedure developed in this study. Method to arrest etching and subsequent preservation of the small diameter taper in mildly alkaline solution was found to be successful.
Comparative effectiveness of topical treatments for hydrofluoric acid burns
Abstract Hydrofluoric acid (HF) burns are characterized by progressive tissue necrosis and severe pain. Numerous topical treatments have been proposed, yet few have been studied experimentally. The present study was designed to examine the comparative efficacy of recommended treatments. Hair on the hind legs of rats was removed and 48 hours later 70% HF was applied. Calcium gluconate, Zephiran (benzalkonium chloride), A + D Ointment, aloe gel, and magnesium ointment were applied topically and burn development was monitored. Calcium gluconate significantly reduced burn size as early as one hour after application. Significant protection continued for seven days after the single application. The other treatments were not effective in decreasing or delaying HF burn development. The results indicated that calcium gluconate ointment was the most effective topical treatment for HF burns
Determination of the Etching Kinetics for the Hydrofluoric Acid/Silicon Dioxide System
Abstract Etching kinetics for several silicon dioxide films in various hydrofluoric acid solutions have been studied. The low temperature silicon dioxide films were deposited at 450°C and 300 mTorr in , , and and annealed at 950°C for 1 h. The thermal oxides were grown at 1100°C in and . Four hydrofluoric acid solutions were used: dilutions of 49 weight percent with deionized water, buffered hydrofluoric acid, surfactant‐buffered hydrofluoric acid, and hydrofluoric acid/hydrochloric acid mixtures. Expressions for etch rate as a function of hydrofluoric acid concentration are presented. Notably, the etching of the low temperature oxides was of the order 1.6–2.0 in solutions and of the order 0.5–1.0 in buffered solutions. The etching of the thermal oxide was of the order 1.37–1.5 in and of the order 0.75–1.07 in buffered solutions. The results for the solutions provide evidence of a two‐part etching mechanism: first, the acidity causes the formation of the silanol bonds on the silicon dioxide surface and, then, the fluorine species react with the silicon to form which is soluble in water and forms . Significant enhancement (as much as 600%) in the etch rate was observed when hydrochloric acid was added to the solutions.
Method for etching a wafer edge using a potassium-based chemical oxidizer in the presence of hydrofluoric acid

A method for fabricating wafers is provided that uses a potassium-based oxidizer in the presence of hydrofluoric acid as the chemical etchant for etching the wafer edge. The potassium-based chemical etchant is preferably potassium permanganate KMnO 4 that is mixed with hydrofluoric acid such that the ratio of hydrofluoric acid to potassium permanganate is between 2:1 and 4:1. The method for fabricating wafers initially divides a crystal ingot into a plurality of wafers before grinding the wafer edge to size and shape the wafer. The wafer can then be subjected to alkaline cleaning and acid etching. After a polysilicon layer is deposited on the wafer for gettering purposes and a silicon dioxide back seal layer, if any, is deposited, the wafer is then etched with the potassium-based chemical oxidizer in the presence of hydrofluoric acid to oxidize and remove the polysilicon layer and any silicon dioxide layer from the edge. The wafer is then rinsed and thermally annealed prior to undergoing edge polishing. In order to concentrate the potassium-based chemical etchant on the wafer edge, the opposed major surfaces can be covered, such as by being stacked in an alternating fashion with spacers. As such, the wafer edge can be reliably formed in an efficient and safe manner.
High-Resolution Imaging of Aromatic Molecules Adsorbed on Rh(111) and Pt(111) in Hydrofluoric Acid Solution:? In Situ STM Study
In situ scanning tunneling microscopy (STM) was employed to study adlayer structures of naphthalene, naphthoquinones, and anthracene on well-defined Rh(111) and Pt(111) electrodes in aqueous HF solutions. All molecules were adsorbed with the flat-lying orientation on both electrodes. Highly ordered adlayers of naphthalene and naphthoquinones were found to form on Rh(111) with the (3√3 × 3√3)R30° structure, while disordered structures were found on Pt(111). Anthracene formed almost close-packed adlayers without long-range ordering. In situ STM disclosed not only the adlayer structure and packing arrangement but also the internal structure of each aromatic molecule. Two- and three-ring structures were clearly discerned for naphthalene and anthracene, respectively. An additional spot was observed for 1,2-naphthoquinone, which was attributed to the oxygen atom at the 2-position.
Hydrofluoric acid burns of the hand: mechanism of injury and treatment
Hydrofluoric acid is one of the strongest inorganic acids and is used extensively in industry and research. It differs from other acids in that the fluoride ion readily penetrates the skin, causing destruction of deep tissue layers and even bone. Authors have previously described numerous topical treatments. This report describes one method of treatment emphasizing immediate skin cleansing and the application of calcium gluconate gel, which is followed by calcium gluconate subcutaneous injections when necessary. An accurate occupational history and physical examination are important aspects of patient assessment. Prompt treatment resulted in relief of pain and a satisfactory clinical result in all cases. A significant delay in treatment was responsible for permanent impairment in 2 of 14 patients.
Hydrofluoric-acid-resistant and hydrophobic pure-silica-zeolite MEL low-dielectric-constant films.
A new technique for the silylation of pure-silica-zeolite MEL low-k films has been developed in which the spin-on films are calcined directly in trimethylchlorosilane or 1,1,1,3,3,3-hexamethyldisilazane (HMDS) in order to protect the films against corrosive wet etch chemicals and ambient moisture adsorption. In an alternative procedure, HMDS is also added to the zeolite suspension before film preparation. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, water-soak tests, and HF etch tests are performed to characterize the films. The dielectric constant is as low as 1.51, and the films resist HF attack up to 5.5 min. These properties are highly desirable by the semiconductor industry for next-generation microprocessors.
Laser‐induced etching of silicon in hydrofluoric acid
Laser‐assisted wet etching (LAWE) ofn‐silicon using a 514.5‐nm line from a cw argon‐ion laser in the presence of hydrofluoric acid is reported. The effects of laser fluence, doping level, and acid concentration on the etch rate are investigated. By LAWE, vias and lines can be rapidly etched with smooth profiles under conditions described
Hydrofluoric Acid-treated T ~ H PF roteins Display the Same Biochemical Properties as Normal T*
The presence of a C-terminal region of 7 within the core of in which there is a significant reduction in the apparent M , PHF (5) raised the possibility that some phosphate groups of T ~ H F(see Fig. l),our results suggest that PHF-1reactivity may not be accessibleto phosphatases.To test thpios ssibility, is associated with phosphorylation events that generate the we disassembled PHF with 8 M guanidine prior to alkaline aberrant M , of 7pHF. phosphatase treatment. As illustrated in Fig. lB, TPHF displays The presence of endogenous degradation products in PHF an apparent M , of 45-63 kDa followingalkaline phosphatase preparations (29) has allowed us to define the approximate treatment of guanidine-treated PHF. Although less extensive location of the PHF-1epitope.Epitope mappinghas indicated mobility changes have been observed with lower concentra- that the T ~ H Fpeptide fragment of <29 kDa is reactive with tions of alkaline phosphatase (data notshown), 100 or 5 mM 746 and is not reactive with more N-terminal 7 antibodies, PPi inhibits the effectof 100units/ml of alkalinephosphatase. Therefore a large part of the reduction in the apparentM , of TPHF can be attributed to theselective removalof phosphate.Because normal 7 contains phosphate groups that are re-including7-1 (9). Since PHF-1 is also reactivewith this TPHFpeptide (Fig. 2B), the PHF-1epitope appears to be in the C -terminal half of 7.Dephosphorylation of TS-Fig. 3A is an Alz 50-reacted im- sistant toalkaline phosphatase and because proteins undergo munoblot that contains PHF from an AD case (lanes 1 and proteolysis in the presence of phosphatases (24), we decided 6 ) and guanidine-treated 7, (lanes 2-5) isolated from a 24- to use an alternative dephosphorylationmethod. In thistudy, year-old human adult. Both alkaline phosphatase and HF we took advantageof the ability of prolonged treatments with treatment result in a less heterogeneouspattern of 7, proteins. HF to dephosphorylateproteins (see Refs.25 and 26). Fig. 1C 7, extracted from normal and AD individuals consist of four (Alz 50 immunoblot)and Fig. 1D (silverstain) illustrate that major and two relativelyminor isoforms of relatively highM , the T ~ H Fproteins display an apparent molecular mass of 43- (30). Becausea similar pattern is observed in alkaline phos- 63 kDa following treatment with 48-50% HF for 16-24 h at phatase- and HF-treated 7. samples (Fig. 3A), the heteroge- 4 "C.Although HF mayremove other modifications, HF- neity observed after HF and alkaline phosphatase treatment treated T ~ H Fis only 1-2 kDa lower in M,than that observed is likelyto reflect the presence of unmodified 7. Note that by when guanidine-treated PHF are incubated with alkaline contrast to TPHF, 7, proteins only undergo slight shifts in M , phosphatase.Therefore,the predominant effectof HF is likely following either alkaline phosphatase orHF treatment. to result from dephosphorylation.Therefore, 7, isolated from normal human adults do notAbnormally Phosphorylated Epitopes of 7pH"Although one study indicated that Alz 50 recognizes a phosphorylated epi- tope (27),the lack of significant changes in the levels of Alz 50 reactivity under different dephosphorylation conditions (Fig. 1)indicates that Alz 50 binding is not dependent upon phosphorylation. This possibility is supported by the recent finding that Alz 50 recognizes the N-terminal region of un- modified T expressed in a bacterial vector (28).Immunoblot analysis using 7-1 (Fig. 2A) illustrates that TPHF is not significantly reactive with 7-1 unless PHFs are pretreated with alkaline phosphatase or HF. Note that alka- line phosphatase treatment of intact PHF is sufficient to expose the 7-1 epitope and that the apparent M , of T ~ H Fis not significantlyreduced under these conditions (see Fig. 1).Fig. 2B is an immunoblot using the monoclonal antibody PHF-1. It illustrates that PHF-1recognizes the 7pHF proteins (lane 1). Although PHF-1 reactivity is not consistently re- duced followingalkaline phosphatase treatment of intact PHF (lane 2), PHF-1 reactivity is consistently reduc

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