Water Treatment

Potash Alum


Potassium alum, potash alum or  tawas is the potassium double sulfate of aluminium. Its chemical formula is KAl(SO4)2 and it is commonly found in its dodecahydrate form as KAl(SO4)2·12(H2O). It is commonly used in water purification,leather tanning, fireproof textiles, and baking powder. It also has cosmetic uses as a deodorant and as an aftershave treatment.



Potassium alum crystallizes in regular octahedra with flattened corners, and is very soluble in water. The solution reddens litmus and is an astringent. When heated to nearly a red heat it gives a porous, friable mass which is known as "burnt alum." It fuses at 92 °C in its own water of crystallization. "Neutral alum" is obtained by the addition of as much sodium carbonate to a solution of alum as will begin to cause the separation of alumina. Alum finds application as a mordant, in the preparation of lakes for sizing hand-made paper and in the clarifying of turbid liquids.




Physical  State(Free from Foreign Matter)

Super White Crystaline Powder and Sugar Crystals

Purity % by Wt.

99% min.

Matter Insoluble in Water

(1% by Wt.)

0.25 (Max.)

Soluble Iron Compounds

(as Fe% by Wt.)

0.007 (Max.)



Potassium as K


Sulfate as SO4




Ph of 5% Solution

Not less than 3

Heavy Metals (as Pb)(% by mass)

0.005 (Max.)


In 50kgs HDPE Bags with Polythene Linier.