Reactive & Functional Polymers 54 (2003) 103–115 www.elsevier.com / locate / react Removal of Cr(VI) by solvent impregnated resins (SIR) q containing aliquat 336 a, b c c * N. Kabay , M. Arda , B. Saha , M. Streat a Department of Chemical Engineering, Ege University, Izmir 35100, Turkey b Department of Chemistry, Ege University, Izmir 35100, Turkey c Department of Chemical Engineering, Loughborough University, Loughborough, Leicestershire, UK LE11 3TU Abstract Solvent impregnated resins (SIR) have been prepared by a wet-impregnation technique using two different polymer matrices, Diaion HP-20 and HP-2MG. Diaion HP-20 possesses a hydrophobic styrene–divinylbenzene polymeric structure whereas HP-2MG is a hydrophilic methacrylic based polymer. Aliquat 336 was employed as the extractant and acetone as the solvent for impregnation. Batch sorption studies have shown that solvent impregnated resins containing Aliquat 336 can be effectively used for the removal of hexavalent chromium from aqueous solutions. The Langmuir adsorption isotherm gave a satisfactory fit of the equilibrium data. A kinetic study has been performed for SIR at two different concentrations of 24 24 Cr(VI) (2 3 10 and 4 3 10 M). A finite-bath diffusion-control model with changing bulk concentration was used for sorption of Cr(VI) by SIR. Increasing the impregnation ratio from 0.5 to 1.0 (g Aliquat 336 / g polymer adsorbent) increased the breakthrough capacity in a column-mode sorption study. The Cr(VI) bound by the SIR has been quantitatively desorbed using 0.1 M NaOH–0.1 M NaCl mixture.  2002 Elsevier Science B.V. All rights reserved. Keywords: Cr(VI); Solvent impregnated resins; Aliquat 336 1. Introduction water thereby preventing the pollution of sur- face and ground water. There is considerable interest in the treatment Chromium compounds are extensively used of polluted water generated by industrial pro- in electroplating, anodizing operations in the cesses. Various technologies have been de- surface finishing industry, corrosion control, veloped over recent years and are now available oxidation, leather industry and various other for the removal of toxic materials from waste- industrial applications. The two common oxida- tion states for chromium in natural water are Cr(III) and Cr(VI). Cr(III) is not a significant q The authors wish to dedicate this paper to the memory of groundwater contaminant whereas Cr(VI) is Professor Abraham Warshawsky. approximately 100 times more toxic than Cr(III) *Corresponding author. Tel.: 190-232-388-7776; fax: 190- [1]. Precipitation is traditionally used for the 232-388-7600. E-mail address: kabay@eng.ege.edu.tr (N. Kabay). treatment of Cr(VI) containing wastewater. This 1381-5148 / 02 / $ – see front matter  2002 Elsevier Science B.V. All rights reserved. PII: S1381-5148(02)00186-4