Cation-Anion ion exchangers are used to produce demineralised water. In this process, it is important that both positively and negatively charged ions are removed. Therefore a treatment in 2 steps is required.
Sometimes the demineralised water of an ion exchanger or RO is not of a sufficient quality and an extra treatment is needed. This is called 'polishing'.
Apart from the standard cation-anion ion exchange, there is a large range of selective ion exchange systems available. These ion exchange-resins are particularly suited to remove specific components out of the water.
