Aluminum Sulphate 18H2O

Gandi Chemical Solutions supplies Aluminum Sulphate 18H2O (CAS 7784-31-8) to mines, concentrators and mineral processing plants. It is supplied as technical grade. Packaging: 25kg. Priced by quotation, with a current safety data sheet on every consignment.

Aluminum sulphate, commonly called alum, is the most widely used coagulant in municipal and industrial water treatment, where it destabilizes suspended particles so they clump together and settle out or filter more easily. It arrives as white crystals, granules, or powder and dissolves readily in water to release the aluminum ions that drive coagulation. Beyond water clarification, it’s also used in paper sizing and various industrial processes that need controlled acidity plus a coagulating effect. It can damage eyes on contact and is mildly corrosive to metals, so standard PPE and corrosion-resistant handling equipment apply.

Where aluminum sulphate 18h2o is used

• Primary coagulant in potable water clarification
• Phosphate removal in municipal wastewater treatment
• Sludge conditioning ahead of dewatering
• Sizing and retention aid in paper manufacture
• Turbidity removal in industrial process water

Key features

• Technical grade. White crystals, granules or powder.
• CAS 7784-31-8, Al2(SO4)3.18H2O.
• Also ordered as Aluminum sulfate octadecahydrate, Patent alum, Cake alum octadecahydrate.
• Supplied in 25kg, with larger units quoted on request.
• Classified Danger (H290, H318). Current SDS ships with every consignment.

Specification and grade

Technical-grade aluminium sulphate octadecahydrate, CAS 7784-31-8, formula Al₂(SO₄)₃·18H₂O, molecular weight 666.43 g/mol, supplied as white crystals, granules or powder. Alum consumes alkalinity as it hydrolyses — roughly 0.5 mg/L as CaCO₃ per mg/L of alum dosed — which is the number that decides whether you also need lime.

Handling and storage

Signal word Danger: H290 may be corrosive to metals, H318 causes serious eye damage. Solutions are acidic and attack carbon steel and concrete, so dosing lines and bunding need to suit. The solid is hygroscopic and cakes in a humid store. Goggles rather than safety glasses for handling, because the eye hazard is the significant one.

Packaging and supply

Standard pack is 25kg. If you are choosing between alum, ferric and polyaluminium chloride, send raw water turbidity, pH, alkalinity and temperature range with the enquiry — that is enough to narrow it to two or three candidates worth a jar test.

References and related supply

• More from this range: Mining Chemicals
• Related products: Zeolite, Activated Carbon, Hydrogen Peroxide 50%
• Independent chemical record: PubChem entry for CAS 7784-31-8