Polyaluminum chloride

Polyaluminum chloride (CAS 1327-41-9), commonly known as PAC or ACH, is an inorganic coagulant used in water treatment and industrial processing.

Where is Polyaluminum chloride used?

• Municipal and industrial water treatment: destabilizes turbidity and organic load, reducing downstream chemical demand compared to alum
• Pulp and paper: retention and drainage aid, improving filler and fiber retention on the wire while controlling pitch deposits
• Paper sizing: precipitant for rosin-based sizing agents, anchoring them to fiber surfaces to improve water resistance
• Textile and leather effluent treatment: precipitates dyes, suspended solids, and COD before discharge
• It neutralizes suspended particles and colloidal matter, enabling their removal through sedimentation or filtration.
• Used for phosphorus removal in lakes to control eutrophication.
• Reduces iron, manganese, and other heavy metals in water.
• Used in mining operations for wastewater clarification.

Good to know: Water treatment grades typically conform to drinking water standards such as those found in the FCC or USP; technical and industrial grades are available for non-potable applications.

Formulation notes

• Maximum recommended dosage for water treatment is 250 g/m3, with a common range of 50-150 g/m3.
• Corrosive to most materials including stainless steel, but can be stored in fiberglass or plastics (polyethylene, polypropylene or polyfluorene).

Typical specification

• Available in grades PAC 28% and PAC 30%.
• Flocculation effectiveness decreases when pH is above 8 and stops at pH 10; optimal pH is up to 7.
• Polyaluminium chloride/chlorosulfate products have an Al2O3 dosage of 10 to 17% and a basicity range of 35 to 75%.
• pH range of 2 to 3.

Storage, packaging and handling

• Store in a dry and ventilated warehouse, with packaging sealed and protected from moisture.
• Must be stored in a corrosion-resistant container with a resistant inner lining.

Frequently asked questions about Polyaluminum chloride

What raw water parameters influence the required dose of polyaluminum chloride?

The amount added depends on raw water properties including turbidity, dissolved organic carbon, temperature and alkalinity.

What distinguishes white polyaluminium chloride from other grades?

White polyaluminium chloride is a high-purity, food-grade product made from high-quality aluminum hydroxide powder and hydrochloric acid.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.