REMOVAL OF Cr (VI) FROM SUDDENLY POLLUTED RAW WATER USING MIEX RESIN: PARAMETERS OPTIMIZATION

Batch experiments were conducted to optimize the process parameters for the removal of Cr (VI) from suddenly polluted raw water using magnetic ion exchange (MIEX) resin through response surface methodology. The second-order polynomial equation including four variables was established to quantitatively predict the removal of Cr (VI) adsorbed on MIEX resin using the response surface methodology. Pareto analysis showed the effect of each term from the model equation was not equally important, and the total first-order terms were the main effect on the Cr (VI) removal, followed by the quadratic and interaction terms. The combined effect of MIEX resin dosage and initial Cr (VI) concentration was more significant than that of initial Cr (VI) concentration and adsorption time. The optimal parameters for the removal of Cr (VI) were found to be 0.96 ml L-1 (dosage), 11.25 mg L-1 (initial Cr (VI) concentration), 5.27 (pH) and 91.08 min (adsorption time), and the removal percentage of Cr (VI) was 99.61% at the optimal conditions. Therefore, MIEX resin is a potential adsorbent for the removal of Cr (VI) from the suddenly polluted raw water.