Degradation of methylene blue utilizing cobalt-impregnated zeolite beta via sulfate radical-based advanced oxidation process

Abstract

Sulfate radical-based oxidation process (SRAOP) is an efficient way to completely degrade toxic dyes from wastewater. The purpose of this study is to utilize zeolite beta to support cobalt ions as a catalyst for such application. Zeolite beta was synthesized hydrothermally with SiO2/Al2O3 ratio of 30. Cobalt was impregnated into zeolite beta via wet impregnation method, with cobalt loading of 2wt% and 5wt% Co2+/zeolite beta. Catalyst characterization was done by XRD, ICP, SEM-EDS, FT-IR, BET, and TPD. Methylene blue was used as model dye to investigate the catalytic capability of the catalyst. The set up for the batch reaction was a 500 mL beaker containing 200 mL of 100 ppm dye mechanically stirred at 300 rpm. Oxone concentration was 2mM and the catalyst loading was varied with concentrations of 0.1, 0.5 and 1 g/L. UV-vis was employed to determine the concentration of dye remaining in the solution. Catalyst particle size ranged from 150 to 300 nm with BET surface area of 576.2 m2/g. The dye exhibited adsorption activity to the zeolite, where 92.4% of the dye were adsorbed after 2 hours. Degradation capability of the catalyst was satisfactory, reaching 100% removal after 45 minutes. The study showed that utilization of zeolite beta as a support for cobalt shows promising results for SRAOP application.