Uses of iron-free aluminum sulfate: Aluminum sulfate is mainly used as a papermaking sizing agent and a flocculant for drinking water, industrial water, and wastewater treatment. It is also a raw material for the production of artificial gemstones and other aluminum salts, such as ammonia alum, potassium alum, and refined aluminum sulfate. In addition, aluminum sulfate is also widely used in clarifiers, petroleum deodorizing and decolorizing agents, concrete waterproofing agents, paper whitening, titanium dioxide post-film treatment, and catalyst carrier production.
The solid product is white, granular or lumpy, with white shiny crystals. Stable in air. Part of the crystal water is lost at 86.5°C, and all crystal water is lost at 250°C. When heated, it expands violently and becomes a spongy substance. When burned to red heat, it decomposes into sulfur trioxide and aluminum oxide. Weathering occurs when the relative humidity is about 25% lower. Easily soluble in water, almost insoluble in ethanol, the solution is acidic. After boiling for a long time, insoluble basic salts precipitate. Relative density 1.62. Iron-free aluminum sulfate is a widely used industrial reagent, often confused with alum (potassium aluminum sulfate dodecahydrate). Aluminum sulfate is usually used as a flocculant in drinking water purification and sewage treatment equipment, and is also used in the paper industry.