Removing Barium and Radium Through Calcium Cation Exchange

The removal of barium (Ba) and radium (Ra), which are found in many groundwater sources, was achieved in laboratory studies with an ion exchange process. In the studies, a strong acid resin in the calcium form effectively removed Ba2+ and Ra2+ to meet standards. The resin was regenerated with reclaimed brine, which would reduce disposal problems in actual practice. Total hardness, alkalinity, pH, and other water quality parameters remained unchanged. Additional research is needed, however, to refine the process and establish the costs.