LED-light-driven over ZnO/biochar nanocomposite for activation of peroxymonosulfate to enhanced photocatalytic removal of methyl orange dye in aqueous solutions

adsorption/desorption. The results of the techniques demonstrated that the well-dispersed ZnO NPs were loaded onto the biochar surface. According to the particle size distribution graph, the average particle size of 64 nm was obtained for the ZnO NPs. BET analyzes showed that pore volume, the specific surface area (SSA) and average pore size of the synthesized nanocomposite increased. The survey of effective operational parameters indicated that the highest photocatalytic activity for MO removal was in the pH 3 of solution, 5 ppm initial dye concentration, 30 mg ZnO/biochar nanocomposite, and 20 mg PMS dose under LED-50W lamp irradiation (97.03% in the reaction time of 80 min). During the process, the reduction of the total organic carbon (TOC) contents and chemical oxygen demand (COD) were observed. Moreover, the MO degradation kinetics under optimal operating conditions were determined. It is concluded that the ZnO@biochar nanocomposite/PMS process was an efficient degradation method for the decomposition of the dye pollutant.