Aluminum sulfate

Aluminum sulfate (CAS 10043-01-3), commonly known as alum or cake alum, is an inorganic salt with the formula Al2(SO4)3. It carries no E-code designation and is traded under several names including filter alum and papermaker's alum. It is registered under REACH and listed in the EC inventory under number 233-135-0.

In water treatment, aluminum sulfate acts as a coagulant by hydrolyzing in water to form aluminum hydroxide flocs that bind suspended particles and carry them out of solution. In pulp and paper production, it functions as a sizing agent by precipitating rosin onto cellulose fibers to control ink absorption. It also serves as a mordant in textile dyeing, fixing colorants to fiber through ionic bonding.

Aluminum sulfate is available in powder and chunk form, with grades meeting industrial, technical, and water treatment specifications including REACH compliance requirements. It is supplied in bulk, big bags, and standard sacked formats to suit varying procurement volumes across European markets.