Sichuan Anion Exchange Resin and Sichuan Cation Exchange Resin Used in Deionization Equipment

　　The purpose of deionization is to remove inorganic ions dissolved in water. Like hard water softener, it is also based on the principle of ion exchange resin. Two kinds of resin - cation exchange resin and anion exchange resin are used here. Sichuan cation exchange resin uses hydrogen ion (H+) to exchange cations, while anion exchange resin uses hydroxide ion (OH-) to exchange anions. Hydrogen ion and hydroxide ion combine to form neutral water. The reaction equation is as follows:

　　M+x+xH-Re_M-M-Re x+xH+1

　　A-z+zOH-Re_A-Rez+zOH-1

　　M + X surface cations, x meter valence, H - Re hydrogen ion exchange between M + X cation and cationic resin, A - Z surface anions, Z meter valence, A - Z and anion exchange resin combined, releasing OH - ions. H + ions combine with OH - ions to form neutral water.

　　These resins need to be reducible after their adsorption capacity is exhausted. Cation exchange resins need strong acid to reduce. On the contrary, anions need strong alkali to reduce. The adsorption capacity of cation exchange resins to various cations is different. Their strength and relative relationship are as follows:

　　Ba 2+ > Pb 2+ > Sr 2+ > Ca 2+ > Ni 2+ > Cd 2+ > CU 2+ > Co 2+ > Zn 2+ > Mg 2+ > Ag 1+ > Cs 1+ > K 1+ > NH4 1+ > Na 1+ > H 1+.+

　　The affinity strength of anion exchange resin with each anion is as follows:

　　S0 2-4+ > I - > NO 3 - > NO 2 - > Cl - > HCO 3 - > OH - > F-

　　If the anion exchange resin in Sichuan is depleted without reduction, the fluorine with weak adsorption will gradually appear in dialysis water, causing cartilage disease, osteoporosis and other bone lesions; if the cation exchange resin is depleted, hydrogen ions will also appear in dialysis water, resulting in an increase in water acidity. Whether the deionization function is effective or not needs to be monitored from time to time. Water quality is generally judged by resistivity or conductivity. Sichuan ion exchange resin used in deionization method can also cause bacterial reproduction and bacteremia, which is worth noting.