Preparation and Characterization of Copper Imprinted PVA/Alginate Based Beads for Removal of Dyes from Aqueous Solution

Cu(II)-imprinted polymeric beads were formed using PVA/SA and adsorption studies were carried out to check the effectiveness of the beads on dye and copper sorption. The adsorption studies were carried out by investigating the point zero charge of the beads which was at 3.04, effect of pH was investigated for methylene blue dye which pH 8 gave the best removal efficiency of about 98% and for copper, pH 5 gave the best removal efficiency, effect of dosage which an increase in dosage resulted to decreased removal efficiency so 0.1 g/L of the beads were used throughout for both adsorbates in this study, effect of initial concentration where removal efficiency increased with increase in initial adsorbate concentration, effect of time in which equilibrium was reached after 360 minutes for methylene blue dye sorption, effect of temperature which revealed that at higher temperatures, methylene blue dye removal efficiency decreased which implies that the adsorption process was exothermic while for copper, it showed it was endothermic. Adsorption kinetic studies were also carried out and it followed a pseudo-second order kinetics while isotherm studies revealed that the study is best described by the Freundlich isotherm which predicts heterogenous adsorption mechanism. From thermodynamic studies, it was deduced from ΔG o and ΔH o values that the process is spontaneous and exothermic for MB and spontaneous but endothermic for copper. Keywords: Cu(II)-imprinted polymeric beads; Adsorption studies; Methylene blue dye; Copper; Adsorption kinetics; Isotherm studies.