The selectivity of ion exchange resin is related to the following factors:
1. The more charge the ion carries, the easier it is to be adsorbed by the anion exchange resin. For example, divalent ions are more easily adsorbed than monovalent ions.
2. For ions with the same charge, ions with large atomic order are more likely to be adsorbed.
3. Compared with the concentrated solution and the dilute solution, the cheap ions in the concentrated solution are easily adsorbed by the resin. Generally speaking, for H-type strongly acidic anion exchange resin, the order of selection of ions in water. For OH type strong basic anion exchange resin, the selection order of anions in water. This selectivity of anion exchange resin is very useful for analyzing and discriminating the process of chemical water treatment.
Resin water quality control:
1. Turbidity of water: downstream flow AC≤5mg/L, convection AC≤2mg/L. Ion exchange resin
2. Residual active chlorine: free chlorine≤0.1mg/L.
3. Chemical oxygen consumption (COD) ≤1mg/L.
4. Iron content: double bed AC ≤0.3mg/L, mixed bed AC ≤0.1mg/L.
After every 10 to 20 weeks of operation, check the contamination status of the anion-cation exchange resin. If pollution is found, it shall be dealt with in a timely manner