Anion exchange

Anion exchange is a process in chemistry and chemical engineering that involves the exchange of anions (negatively charged ions) between a solution and a solid, often a resin. This process is a key component of many industrial processes, including water purification, pharmaceutical manufacturing, and the production of certain types of synthetic materials.

Overview

Anion exchange is a type of ion exchange, a broad category of processes that also includes cation exchange. In anion exchange, the substance that undergoes the exchange (the exchanger) is typically a solid resin that contains positively charged sites. These sites attract and bind anions from the surrounding solution, releasing other anions in the process.

The efficiency and selectivity of anion exchange can be influenced by a variety of factors, including the nature of the anions involved, the properties of the exchanger, and the conditions of the exchange process (such as temperature and pH).

Applications

Anion exchange is used in a wide range of applications. In water treatment, it is used to remove anions such as chloride, nitrate, and sulfate from water, improving its taste and safety. In the pharmaceutical industry, anion exchange is used to purify drugs and other products. It is also used in the production of synthetic materials, such as plastics and resins.

See also

• Ion exchange
• Cation exchange
• Water treatment
• Chemical engineering