Determination of parameters and kinetic evaluation for chromium (VI) removal using four resins

Abstract

This research aimed to identify optimal studied variables for chromium (VI) removal using four resins (IRA 96, IRA 400, DOWEX 1x8, and LEWATIT). A 1,5-diphenylcarbazide method was used for the quantification of chromium (VI). A factorial design with triple replication at the center point was used to evaluate pH, resin dose (g/100 mL), and initial chromium (VI) concentration. The optimal values for the four resins were a pH of 3, a resin concentration of 0.15 g/100 mL of solution, and an initial concentration of 10 mg/L of chromium. Then, an ANOVA study was done to compare the resins results using a p-value <0.05. The DOWEX resin presented the highest removal percentage (98.39%) for a reaction period of 45 minutes, with an exponential model that fits a pseudo-first-order kinetics with a coefficient of determination equal to 0.967.

Keywords

• resins
• dowex
• chromium (vi)
• pseudo first order
• kinetics