What Is Ammonium Sulfate?
Ammonium sulfate, an ammonium salt of sulfuric acid, has the chemical formula (NH4)2SO4. It is a white, odorless, crystalline solid with a slightly acidic pH of 4.5 to 5.0. Upon heating, it decomposes at 120°C and melts at 357°C, releasing ammonia. Industrially, it is produced by reacting sulfuric acid with ammonia.
Uses of Ammonium Sulfate
Primarily used as a nitrogen fertilizer in agriculture, ammonium sulfate is essential for plant growth. Its quick absorption by plant roots and low cost make it a popular choice. It is also used to harden snow at ski resorts and precipitate proteins in biochemical applications.
Properties of Ammonium Sulfate
With a molecular weight of 132.14, ammonium sulfate is soluble in water and virtually insoluble in ethanol. It decomposes upon heating, forming various compounds and eventually decomposing into ammonia, sulfur dioxide, and nitrogen.
Structure of Ammonium Sulfate
This ionic compound consists of two ammonium ions (NH4+) and one sulfate ion (SO42-), showcasing a typical ionic bond structure. The ammonium ion features one nitrogen atom surrounded by four hydrogen atoms, and the sulfate ion comprises a sulfur atom bonded to four oxygen atoms.
Other Information on Ammonium Sulfate
Ammonium Sulfate Production Methods
1. Synthetic Method: A neutralization reaction between sulfuric acid and ammonia. This method is preferred for producing pharmaceuticals and reagents due to its operational advantages.
2. Byproduct of Coke Production: Produced by reacting discharged ammonia during coke production with concentrated sulfuric acid.
3. Caprolactam Synthesis Byproduct: Generated as a byproduct in the production of caprolactam, a nylon precursor, through several chemical reactions, including the oxidation of cyclohexane and Beckmann rearrangement.
4. Acrylamide Synthesis Byproduct: Formerly produced as a byproduct of acrylonitrile hydrolysis using sulfuric acid as a catalyst, though less common now due to enzymatic processes.
5. Coal Boiler Emissions Treatment: Formed by reacting sulfur dioxide gas from coal combustion with ammonia.