Packed column study of the sorption of hexavalent chromium by novel solvent impregnated resins containing aliquat 336: Effect of chloride and sulfate ions

Packed column studies were performed with uncoated SIRs in contact with a 4 x 10(-4) M K2CrO4 solution at different pH values. The breakthrough capacity was greater at pH 4 than at pH 8. The sorption performance of uncoated and coated (highly crosslinked surface layer) SIR were compared over five column-mode sorption-elution cycles. The shift in the chromium breakthrough point was negligible for coated SIRs. These results confirm that the loss of Aliquat 336 from within the coated SIRs was small. Column-mode sorption of chromate ions by Aliquat 336 containing solvent impregnated resins in the presence of chloride and sulfate ions has also been studied at pH 4. These sorption results were compared with those obtained for a strong base anion exchange resin (Amberlite IRA 904) under identical conditions. There was a small decrease in total Cr(VI) capacity of the SIRs in the presence of chloride ions. However, the effect of sulfate ions was slightly greater and almost identical for Amberlite IRA 904 and SIRs. (c) 2005 Elsevier B.V. All rights reserved.