Ammonium bifluoride is a white or colorless, odorless, crystalline compound with the formula NH4HF2. Ammonium bifluoride, a strong acid, is used in many fields in industry and daily life. Ammonium bifluoride is produced from ammonia and hydrogen fluoride. This colorless salt is a glass corrosive and an intermediate in the once thought pathway to hydrofluoric acid. The chemical and physical properties of ammonium bifluoride are as follows:

• Its molecular weight is 57.04 g/mol.
• Melting point is 125.6 °C.
• Boiling point is 240 °C.
• Its density is 1.50 g/mL.
• Solubility is high in water and alcohol, low in ether.
• pKa value is 3.5.

The production methods of ammonium bifluoride are as follows:

• Reductive ammoniation method with hydrogen: This is the most common production method of ammonium bifluoride. It can be prepared by hydrogen reducing ammoniation of diethylene glycol. Water is also produced in this method.
• Sulfuric acid method: This method is an alternative production method of ammonium bifluoride. Diethanol can be prepared by dehydrogenation of amine with a strong acid. This method also produces water and ethanol.
• Bis (chloroethyl) ether method: This is an old method of production of ammonium bifluoride. It can be prepared by heating bis (chloroethyl) ether in excess of ammonia. This method also produces hydrochloric acid and ethylene glycol.

Uses of ammonium bifluoride include:

• Glass industry Ammonium bifluoride is one of the most widely used abrasives in the glass industry. It attacks the silica component of glass, shaping rough glass into a smooth shape. For example, ammonium bifluoride is used to write on glass bottles or to pattern glass surfaces.
• Electronic industry: Ammonium bifluoride also plays an important role in the electronics industry. Ammonium bifluoride is used for cleaning, soldering and coating circuit boards.
• Food industry Ammonium bifluoride is also used for various purposes in the food industry. Ammonium bifluoride is used to sterilize milk and dairy equipment and to purify beer dispensing tubes and various parts.
• Ceramic industry: Ammonium bifluoride is also used in the ceramic industry. Ammonium bifluoride is used for leavening, firing and polishing ceramic paste.
• Petroleum industry Ammonium bifluoride is also used in the oil industry. Ammonium bifluoride is used for drilling oil wells, cleaning and protecting the oilfield refill water system.
• Cleaning industry Ammonium bifluoride is also used as an effective agent in the cleaning industry. Ammonium bifluoride is used to remove rust from metal surfaces, remove lime stains and prevent bad odors.