Separation and Purification Technology, Vol.33, No.2, 179-187, 2003
Removal of chromates from drinking water by anion exchangers
Strong-base anion-exchange resins were used for selective removal of Cr(VI) from tap water. The influence on the process efficiency of parameters, such as the type of anion-exchange resin, the concentrations of Cl- and SO42- in the 4 feed water, and the flow rate and pH of the feed water, was investigated. Regeneration was carried out by the reduction of the chromate with bisulfite under acidic conditions and the subsequent removal of the Cr from the column as the Cr3+ cation. The pH of the regenerant solution was then increased, causing Cr(OH)(3) to precipitate, and the precipitate was removed by filtration. (C) 2003 Elsevier B.V. All rights reserved.