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Aluminium potassium sulphate - is a chemical compound: the potassium double sulfate of aluminium. Its chemical formula is KAl(SO4)2 and it is commonly found in its dodecahydrate form as AIK(SO4)2.12H2O.
A 1775 (OTTO) Aluminium potassium sulphate, 99% Cas 7784-24-9 - used in tanning of leather to prepare the hide.