Chromium removal from water using granular ferric hydroxide adsorbents: An in-depth adsorption investigation and the optimization

摘要

Adsorption of hexavalent chromium (Cr(VI)) by granular ferric hydroxide (GFH) and the kinetics were optimized for maximum removal efficiency using the Taguchi approach. The results displayed that the obtained data are well fitted to the BET isotherm implying physicochemical multilayer adsorption of Cr(VI). The adsorbent at the optimum condition (pH = 5, initial concentration of Cr(VI) at 20 mg L-1, contact time at 60 min, and GFH dose at 0.75 g in 50 mL of Cr(VI) solution) provides up to 100% removal capability. Besides, desorption experiments were carried out using 50 mL of 0.1 M NaOH as a stripping solution.