Arsenic Removal from Groundwater by Iron Impregnated Sand

A granular media known as iron impregnated sand (IIS), developed in the laboratory by impregnating iron on a quartz sand surface by a simple and easy process has proved more effective than iron oxide coated sand (IOCS). Kinetic and isothermal studies showed that the uptake potential of IIS media was much more than IOCS media. The sequence of anions studied competing with respect to As(III) on IIS media was SO42?>HCO31?>Cl?. The presence of Ca2+ ions significantly improved the removal efficiency. During column studies the breakthrough loadings of IOCS (qb = 0.042 and 0.068) and IIS (qb = 0.097 and 0.217) for water and simulated water, respectively, show that qb for IOCS is lower than for IIS under similar experimental conditions. A filter effluent of 68 L of simulated water passed through 250 g IIS contained less than 0.05 mg As/L.