Strong base anion exchangers remove bicarbonate, as illustrated by the following reaction:
The principal regenerant is sodium chloride. Capacities can be increased by adding a small proportion of caustic soda to the salt. This process eliminates the need for acid-proof equipment and offers convenience, low cost, and a relatively small space requirement. In addition to bicarbonate removal, reductions in sulfate, nitrate, phosphate, anionic surfactants and color are also achieved. However, the effluent chloride level increases in the exchange.
Was this article helpful?