Efficiency of Response Surface Methodology for Optimizing Removal of Cu2+ from Aqueous Solution Using Modified Glass Beads in a Fixed-Bed Column

Heavy metals are among the significant pollutants of water sources. Unlike organic contaminants, they are not biodegradable and tend to accumulate in living organisms. The objective of the present work was to investigate efficiency of glass beads modified with APTES ligand (3-aminopropyltriethoxysilane) on copper ion removal from aqueous solution. Methodology of the research was experimental, basic and applicable based on the nature of the study and experimental data. Response surface methodology based on Box-Behnken design was used to assess the effect of independent variables including flow rate, solution pH, initial concentrations and size of glass beads on the response function (removal efficiency of copper ion). The optimum conditions to remove copper ion from aqueous solution was achieved at pH≥6, flow rate of 30 ml min−1, and a glass beads size of 38-63µ. Absorption results indicated that Cu2+ adsorption from aqueous solutions to fit with Langmuir isotherm and follow pseudo-second-order kinetic model. All the results demonstrated that modified glass beads successfully absorb copper ion from aqueous solution.