Ammonium Sulfite was a byproduct of gas scrubbers in the past. Ammonium Sulfite in water is now used to co-produce the product by the reaction of ammonia and sulfur dioxide. In food, Ammonium Sulfite creates adds caramel coloring and the compound is also used as a preservative for fixers in photography. In the cosmetics industry, it is used to straighten hair ore create a hair waving affect. Additional uses of Ammonium Sulfite include the production of lubricants for cold metal working to reduce friction to keep heat production down and keep impurities out of the metals.
Ammonium Sulfite Formula - NH4)2SO
Percent composition - Nitrogen 24.1%, Oxygen 41.3%, Sulfur 27.6% and Hydrogen 6.9%