Aluminum sulfate (chemical formula: Al2(SO4)3) is a widely used industrial reagent, often confused with alum. Aluminum sulfate is usually used as a flocculant in the purification of drinking water and sewage treatment equipment, as well as in the paper industry. Under natural conditions, aluminum sulfate hardly exists in the form of anhydrous salts. It forms a series of hydrates, of which aluminum sulfate hexahydrate is the most common. Aluminum sulfate is also a very effective mollusk insecticide, killing Spanish slugs.
Chemical properties
It is very soluble in water. Aluminum sulfate is insoluble in pure sulfuric acid (only coexists), and is dissolved in water together with sulfuric acid in sulfuric acid solution. Therefore, the solubility of aluminum sulfate in sulfuric acid is the solubility of aluminum sulfate in water.





Product name | Aluminium sulfate |
CAS | 10043-01-3 |
chemical formula | Al2(SO4)3 |
Molecular weight | 342.151 |
Density | 2.71 g/cm³ |
Melting point | 770 ºC |
Appearance | White crystalline powder or flake particles |




Water treatment : It's used for purification of drinking water and wastewater treatment
paper industry : It helps in sizing of paper at neutral and alkaline pH, thus improving paper quality and sizing efficiency.
Textile Industry : It is used for color fixing in Naphthol based dyes for cotton fabri.
Other use: Leather tanning, lubricating compositions, fire retardants; decolorizing agent in petroleum,deodorizer; foodadditive; firming agent etc