Introduction of Ion Exchange Resin Modification in Sichuan

　　Modification of Sichuan Cation Exchange Resin

　　The deterioration of cation exchange resin in application is mainly due to the presence of oxidants in water, such as free chlorine and nitrate. When the temperature is high, the resin is more seriously eroded by oxidants. If there are heavy metal ions in the water, the resin can accelerate deterioration because of its catalytic role.

　　The phenomena after oxidation of cation exchange resin are as follows: the color becomes lighter, the volume of resin becomes larger, so the fragility and volume exchange capacity decrease, but the mass exchange capacity does not change much. Because the order of contact between upper and lower resin layers and influent is different, the degree of damage is also different. When underwater flow, the upper resin first contacts with water containing oxidant, so the degree of damage is great.

　　Practice has proved that strong acidic H-type resin is severely damaged. There are two commonly used methods to remove free chlorine in water, one is to filter with activated carbon, the other is to add sodium sulfite.

　　Macroporous strong acid cation exchange resin is better in terms of oxidation resistance and mechanical strength, while exchange capacity, regeneration efficiency and sodium leakage are almost the same as those of gel type resins.

　　Modification of Sichuan Anion Exchange Resin

　　Generally speaking, the chemical stability of anion exchange resin is worse than that of cation exchange resin, so its resistance to oxidant and high temperature is also worse. But anion exchanger is usually arranged in the desalting system after the cation exchange, and the strong oxidant in the water entering the desalting device is consumed on the oxidized cation exchange resin, invisibly on the anion exchange tree. Lipids play a protective role. Oxygen dissolved in water generally destroys anion exchange resins.