Aluminumsalter

Aluminumsalter are chemical compounds that consist of aluminum ions, typically Al3+, paired with various anions to form salts. Common examples include aluminum sulfate (Al2(SO4)3), aluminum chloride (AlCl3), aluminum nitrate (Al(NO3)3), and alum, the potassium aluminum sulfate KAl(SO4)2·12H2O. The solubility and behavior of these salts depend on the counterion and the pH of the solution.

In water chemistry, aluminum salts are widely used as coagulants. When added to raw water, they hydrolyze to form gelatinous aluminum hydroxide, which helps to trap suspended particles and dissolved organic matter. This process promotes rapid settling or flotation and is a standard step in municipal water treatment and some waste-water applications. Aluminum sulfate and related coagulants are chosen for their effectiveness in clarifying water and removing color and turbidity.

Aluminum salts also appear in other applications. Aluminum chlorohydrate and related compounds are used in antiperspirants to reduce sweating by forming temporary plugs in sweat ducts. In the textile and paper industries, aluminum salts can act as mordants or processing aids. They may also be encountered in laboratory settings as reagents or precursors to other aluminum compounds.

Safety and environmental considerations are important. Aluminum salts can be corrosive in concentrated forms and may irritate skin, eyes, or the gastrointestinal tract. In water and soil, they can affect pH and, at high levels, aquatic life. Regulatory guidance governs their use and disposal, with ongoing assessment of health and environmental risks associated with aluminum compounds.