Removal of chromium (VI) by commercial anion exchange membrane BII from an aqueous solution: Adsorption kinetic, equilibrium and thermodynamic studies

Abstract

This work reports chromium (Cr(VI)) adsorption from an aqueous solution onto anion exchange membrane (AEM) BII. The Cr(VI) percentage adsorption was increased from 71 to 82 %, 70 to 92 % and 72 to 86 % with BII membrane dosage, contact time, and temperature respectively while decrease 93 to 84 % with Cr(VI) initial concentration. Kinetic illustration showed that Cr(VI) adsorption obeyed pseud-second-order model. Isotherm illustration denoted that Cr(VI) adsorption onto BII membrane fitted to Langmuir isotherm because correlation coefficient (R2 = 0.992) was close to unity. Moreover, determined mean adsorption energy (E = 2.78 KJ/mol) value represented that Cr(VI) adsorption onto BII membranes was physical adsorption process. Measured value of enthalpy (ΔH° = 13.59 KJ/mol) suggested that it was endothermic process. In addition, the determined of Gibb’s free energy (ΔG°) value for Cr (VI) adsorption revealed that it was spontaneous and feasible process.