Treatment of perchlorate-contaminated groundwater using highly selective: regenerable ion-exchange technology: a pilot-scale demonstration

摘要

Treatment of perchlorate-contaminated groundwater using highly selective, regenerable ion-exchange technology has been recently demonstrated at Edwards Air Force Base, California. At an in fluent concentration of about 450 μg/l (ClO{sub}4){sup}-, the bifunctional anion-exchange resin bed treated approximately 40,000 empty bed volumes of groundwater before a significant breakthrough of (ClO{sub}4){sup}- occurred. The presence of relatively high concentrations of chloride and sulfate in site groundwater did not appear to affect the ability of the bifunctional resin to remove (ClO{sub}4){sup}-. The spent resin bed was successfully regenerated using the FeCl{sub}3-HCl regeneration technique recently developed at the Oak Ridge National Laboratory and nearly 100 percent of sorbed (ClO{sub}4){sup}- was displaced or recovered after elution with as little as about two bed volumes of the regenerant solution. In addition, a new methodology was developed to completely destroy (ClO{sub}4){sup}- in the FeCl{sub}3-HCl solution so that the disposal of perchlorate-containing hazardous wastes could be eliminated. It is therefore anticipated that these treatment and regeneration technologies may offer an efficient and cost-effective means to remove (ClO{sub}4){sup}- from contaminated groundwater with significantly reduced generation of waste requiring disposal.