What Is Hydrogen Fluoride?

Hydrogen fluoride, chemical formula HF, is a binary compound consisting of fluorine and hydrogen. It is a colorless, irritating gas ^[1] . Hydrogen fluoride is a monovalent weak acid. Hydrogen fluoride and its aqueous solutions are toxic, which can easily deform bones and teeth. Hydrofluoric acid can be absorbed through the skin by the mucous membranes, respiratory tract and gastrointestinal tract. After poisoning, it should be treated immediately and sent to a doctor. When mixed with antimony pentafluoride, fluoroantimonic acid (HSbF6) is formed.

Fluorochemicals is one of the emerging and key fine chemical industries in China. Fluorochemical products mainly include raw materials of fluorine refrigerants, high-efficiency fire extinguishing agents, fluorine-containing plastics, fluorine-containing coatings, and fluorine-containing surfactants. They are also used to produce various inorganic salts such as ammonium fluoride and ammonium hydrogen fluoride. According to data, the world s hydrogen fluoride production reached 5 million tons in 2005, and China s output accounted for about 10% of the world s total. With the development of the national economy, the domestic demand for fluorine chemical products is also increasing, and the expansion of domestic and foreign markets has further accelerated the development of China's fluorine chemical industry. The hazardous chemicals involved in fluorinated chemical products are various, volatile, highly toxic, and corrosive, as well as the danger of fire and explosion. In the production process of many fluorides, the residual fluorine gas hydrolysis or as a by-product of the production reaction will inevitably contain a small amount of hydrogen fluoride. For some high-purity fluorides, the content of hydrogen fluoride will directly affect the quality of the product.

With the continuous improvement and development of analytical instruments, the analysis technology of hydrogen fluoride has also undergone considerable development and progress, and its analysis precision and accuracy have been greatly improved. The hydrogen fluoride analysis methods developed in recent years mainly include fluorescence analysis, emission spectrometry, flow injection system method, and Fourier infrared spectroscopy.

1. Mainly used as a raw material for fluorinated compounds and also used for

Skin contact: Remove contaminated clothing immediately and rinse with plenty of running water for at least 15 minutes. Seek medical attention.

Eye contact: Immediately lift the eyelids and rinse thoroughly with plenty of running water or saline for at least 15 minutes. Seek medical attention.

Hazardous characteristics: Hydrogen fluoride is a highly reactive substance and can react with various substances. Extremely corrosive.

Fire fighting methods: Firefighters must wear special protective clothing and operate in shelters. Spray water to keep the fire container cool until the fire is over.

Emergency treatment: Quickly evacuate personnel from the leaked contaminated area to a safe area, and immediately isolate 150m, and strictly restrict access. Emergency personnel must wear protective equipment. Cut off the source of the leak if possible. Prevent from flowing into restricted spaces such as sewers and flood drains. If it is a gas, ventilate it reasonably and accelerate the diffusion. Spray with ammonia or other dilute lye to neutralize it. Construct a large amount of waste water from dykes or pits. Residual or leaked air can also be sent to a water washing tower or a fume hood connected to the tower by an exhaust fan. The leaking container should be properly handled, and used after repairing and inspection. If it is liquid, absorb or absorb it with sand or other non-combustible materials. It can also be rinsed with a large amount of water and diluted into the waste water system. If there is a large amount of leakage, build a dyke or dig to contain it. Use a pump to transfer to a tanker or a special collector, immediately cut off the source of the leak, remove the container to a safe area, identify the site of the leak, prevent the expansion of pollution and secondary pollution, and emergency treatment appliances, the site, and wastewater should continue Carry out harmless treatment to meet environmental protection requirements. ^[6]

Health hazards: It has a strong irritating and corrosive effect on the respiratory mucosa and skin.

Acute poisoning: Inhalation of higher concentrations of hydrogen fluoride can cause eye and respiratory tract mucosal irritation symptoms. In severe cases, bronchitis, pneumonia or pulmonary edema can occur, and even reflex asphyxia occurs. Eye contact with severe local pain, severe corneal damage, and even perforation. Hydrofluoric acid skin is flushed and dry in the early stage of skin burns. The wound was pale, necrotic, and then purple-black or gray-black. Deep burns or improper treatment can form deep ulcers that are difficult to heal and damage the periosteum and bone. This product has severe burns and pain. Chronic effects: irritation of the eyes and upper respiratory tract, or nasal irritation, and decreased smell. May have tooth erosion. Bone X-ray abnormalities and industrial fluorosis are rare.

Explosion hazard: This product is non-combustible, highly toxic, highly corrosive and irritating, and can cause burns to the human body.

Respiratory protection: When the concentration in the air exceeds the standard, you must wear a gas mask or an air supply helmet. Protective equipment must be worn when rescue or escape in an emergency.

Eye protection: Wear chemical safety protective glasses.

Protective clothing: Wear work clothes (made of anticorrosive materials).

Hand protection: Wear rubber gloves.

Other: After work, shower and change clothes. Store clothes contaminated by poisons separately and wash them before reuse. Maintain good hygiene

Precautions for operation: Closed operation, pay attention to ventilation. Operations are as mechanized and automated as possible. Operators must be specially trained and strictly abide by the operating procedures. It is recommended that the operator wear a self-absorption filtering gas mask (full face mask), wear rubber acid and alkali resistant clothing, and rubber acid and alkali resistant gloves. Avoid generating fumes. Prevent gas or vapor from leaking into the workplace air. Keep away from flammable and combustible materials. Lightly load and unload during transportation to prevent damage to cylinders and accessories. Equipped with leakage emergency treatment equipment. Empty containers may be harmful residues.

Storage precautions: Store in a cool, ventilated warehouse. Keep away from fire and heat sources. The storage temperature should not exceed 30 . It should be stored separately from flammable (combustible) materials and edible chemicals. The storage area should be equipped with emergency response equipment. The "five double" management system for extremely toxic substances should be strictly implemented. ^[6]