Experimental design and RSM modeling of tetracycline photocatalytic degradation using rGO/ZnO/Cu

Abstract

ABSTRACT Tetracycline (TC) photodegradation using rGO/ZnO/Cu nano-powder was investigated under visible irradiation. The effect of operating conditions such as pH, photocatalyst concentration, and initial concentration of pollutant on reaction rate constant and total organic carbon (TOC) removal was studied. Complete removal of 40mg/L tetracycline concentrations was achieved at pH 8 and 1 g/L rGO/ZnO/Cu. The best model fitted to the experimental data was pseudo-second-order, with maximum and minimum kinetic rate constants of TC elimination estimated at 1 g/L (0.007280 L/min/mg) and photolysis (0.000018 L/min/mg), respectively. The TC and TOC removal percentages reached 100% and 91.2% after 180 and 300 min, respectively.