Removal of Cu2+ ions from aqueous solutions using modified stalk of Ricinus communis L. in a batch and fixed bed column: Optimization using statistical design methods

RESUMO – This work investigates the ability of modified stalk of Ricinus communis L., an agricultural biomaterial, to remove Cu ions from aqueous solution in a batch and fixed-bed column. Batch biosorption experiments indicated that the aximum adsorption capacity calculated by Langmuir model (qmax) was 131.04 mg/g for for MMB. Three significant variables (bed height, flow and initial concentration) were selected for further optimization via response surface methodology (RSM) based on Box–Behnken model. A statistically quadratic model was constructed on basis of which the threedimensional response surfaces were plotted.