ioonivahetusvaik

Ioonivahetusvaik, also known as ion-exchange resin, is a type of insoluble granular material with highly developed surface area. These materials are typically porous polymers that contain charged functional groups. These functional groups can attract and bind ions of opposite charge from a solution, while releasing ions of the same charge in exchange. This process is known as ion exchange.

Ion-exchange resins are widely used in various applications, including water purification, water softening, separation and purification of chemicals, and in chromatography. In water treatment, for instance, they are employed to remove undesirable ions such as calcium and magnesium, which cause hardness, or heavy metals like lead and mercury. The resin beads are typically made from polystyrene or cellulose and are functionalized with ion-exchange groups like sulfonic acids (-SO3H) for cation exchange or quaternary ammonium groups (-N(CH3)3+OH-) for anion exchange.

The performance of an ion-exchange resin depends on factors such as its chemical structure, particle size, porosity, and the specific functional groups present. The process of regeneration is crucial for the reuse of ion-exchange resins. This involves treating the exhausted resin with a concentrated solution of ions that have a higher affinity for the functional groups than the ions that have been removed from the solution. This reverses the ion-exchange process and restores the resin's capacity to remove ions.