The use of waste welding powders as catalysts in dye and Cr(VI) removal by fenton-like process

The textile industry is a sector whose use has become widespread with the development of the industry. Colored wastewater is produced from various processes used in the textile industry. The treatment of these wastewaters is quite difficult due to their complex and stable structure. Waste minimization is one of the important issue nowadays. In this study, the usability of waste welding powders (WWP) was investigated in the Fenton-like process and Reactive Orange 16 (RO16) dye removal from aqueous solution. Solution pH, amount of catalyst, amount of H2O2, initial pollutants concentrations, reaction time and temperature parameters were optimized. 100% RO16 dye removal efficiency was obtained at pH: 2, dye concentration: 100 mg/L, catalyst amount: 1 g/L, and H2O2 amount: 2.5 μL/L. Besides, 99.7% Cr(VI) removal efficiency was obtained at pH: 2, Cr(VI) concentration: 10 mg/L, catalyst amount: 0.25 g/L, and H2O2 amount: 2.5 μL/L. In addition, the characterization of WWP was also carried out by SEM, EDX, XRD and zeta potential analyses. WWP can be considered to be a viable catalyst for both dye and Cr(VI) removal from aqueous solution. After WWP's optimization experiments with synthetic wastewater were completed, it was tested on real wastewater. As a result of experiments with real wastewater, 100% removal efficiency was obtained in textile wastewater at 60 min and 100% removal efficiency in wastewater containing Cr(VI) at 45 min. This has revealed that WWP is a promising catalyst for the treatment of real wastewater.