anion exchange

chemical reaction

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June 18, 2026

Quick Summary

Anion exchange is a chemical process where anions (negatively charged ions) are exchanged or removed from a solution. This can involve substituting one type of anion for another, or adsorbing anions onto a basic substance.1

Ion-exchange reactions, including anion exchange, are fundamental to many industrial and laboratory applications. A key use is in water treatment, where ion-exchange resins can remove unwanted ions, such as those causing hardness in water, or deionize water completely. In the laboratory, anion exchange is employed for separating metal ions and analyzing complex biological molecules. These reactions are reversible and their behavior can be described by equilibrium constants, which are influenced by factors like ion charge and concentration.234

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clay mineral
Ion exchange
…to adsorb certain cations and anions and retain them around the outside of the structural unit in an exchangeable state, generally without affecting the basic silicate structure. These adsorbed ions are easily exchanged by other ions. The exchange reaction differs from simple sorption because it has a quantitative relationship between…
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…to adsorb certain cations and anions and retain them around the outside of the structural unit in an exchangeable state, generally without affecting the basic silicate structure. These adsorbed ions are easily exchanged by other ions. The exchange reaction differs from simple sorption because it has a quantitative relationship between…
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ion-exchange reaction
Ion-exchange materials
…and are said to undergo anion exchange.
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…and are said to undergo anion exchange.
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mineral
Compositional variation
Simple cationic or anionic substitutions are the most basic types of substitutional solid solution. A simple cationic substitution can be represented in a compound of the general form A⁺X⁻ in which cation B⁺ replaces in part or in total cation A⁺. Both cations in this example have the…
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Simple cationic or anionic substitutions are the most basic types of substitutional solid solution. A simple cationic substitution can be represented in a compound of the general form A⁺X⁻ in which cation B⁺ replaces in part or in total cation A⁺. Both cations in this example have the…
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