... mordant,tanning agents, pharmaceuticals astringent, wood preservatives, foam fire extinguishing agent 2.with ISO 9001 Aluminum sulphate powder Aluminum Sulfate Synonyms ... .2.Specification (according to HG2227-91):(1)Al2O3, % more than 15.6%(2)Fe, % less than 0.7% or non-ferric(3 ... %(4)Water insoluble substances, % less than 0.15%(5)As, % less than 0.0005(6)Heavy metal (Pb), % less than 0.002 ...