Ammonium aluminium sulfate, also known as ammonium alum or just alum, is a white crystalline double sulfate usually encountered as the dodecahydrate, formula (NH4)Al(SO4)2·12H2O. It is used in small amounts in a variety of niche applications. The dodecahydrate occurs naturally as the rare mineral tschermigite .
insoluble in water,(%)
1.It is used in water purification, in vegetable glues, in porcelain cements, in deodorants and in tanning, dyeing and in fireproofing textiles.
2.Ammonium alum is a common ingredient in animal repellant sprays.
3.In industrial,It is used in leather, processing of washing powder, feed processing, pencil production.