Ion exchange is feasible for desalination

Developments in processes for demineralization by ion exchange are discussed, including the Desal process (see Wat. Pollut. Abstr., 1968, 41, Abstr. No. 1490), the Sirotherm process (see Wat. Pollut. Abstr., 1967, 40, Abstr. No. 199), and the SUL-BI-SUL process, developed by Nalco Chemical Co., in which a strongly acidic, sulphonic cation-exchange resin, which is regenerated with sulphuric acid, is followed by a basic quaternary ammonium anion-exchange resin in the sulphate form, which removes the acids produced by cation exchange by using the hydrogen to convert the resin to the bisulphate form processes discussed are those using an ion-exchange liquid consisting of organic removal of magnesium, and the process of continuous ion exchange developed by the Asahi Chemical Co. of Japan.