Aluminium sulfate

Aluminium sulfate is a chemical compound with the formula Al₂(SO₄)₃. It is soluble in water and is mainly used as a coagulating agent in the purification of drinking water and waste water treatment plants, and also in paper manufacturing.

Chemical properties

Aluminium sulfate is an aluminium salt that is mainly used as a coagulating agent. It is a white crystalline solid in its anhydrous form and becomes octadecahydrate (Al₂(SO₄)₃*18H₂O) when hydrated. It has a sweet, mildly astringent taste and is also known as papermaker's alum due to its use in the papermaking process.

Production

Aluminium sulfate is produced by reacting sulfuric acid with bauxite or other forms of aluminium hydroxide. The reaction leads to the formation of aluminium sulfate and water. The process can be represented by the following chemical equation:

2 Al(OH)₃ + 3 H₂SO₄ → Al₂(SO₄)₃ + 6H₂O

Uses

Aluminium sulfate is widely used in water treatment plants for the purification of drinking water. It acts as a coagulating agent, causing the impurities to form into larger particles that can be easily removed from the water. It is also used in the paper industry to size paper and control pH. Other uses include as a mordant in dyeing and printing textiles, and in the manufacturing of fire extinguisher compounds, cosmetics, and pharmaceuticals.

Health effects

Exposure to aluminium sulfate can cause skin and eye irritation. Ingestion of large amounts can lead to stomach upset, nausea, and vomiting. Long-term exposure can lead to more serious health effects such as lung damage and neurotoxicity.

See also

• Aluminium
• Sulfuric acid
• Water treatment
• Papermaking