Photocatalytic degradation of aqueous rhodamine B by TiO2/ZnO/rGO nanocomposite: photocatalytic activity and catalytic mechanism

The present study evaluated fabrication of bioactivated carbon (BAC) from waste activated sludge (WAS) for methyl tert-butyl ether (MTBE) removal from aqueous solution. BACs were prepared using KOH, H 3 PO 4 , and ZnCl 2 as chemical activation reagents, followed by thermal activation. Batch experiments with different BAC types and dosages, solution pH, initial MTBE concentrations, and contact times were conducted to investigate the BAC effectiveness. The obtained data were analyzed using the kinetics and isotherm model and also with artificial neural network (ANN). The result of Fourier transform infrared (FTIR) spectra of WAS and BAC was depicted that the C–H and C–C were major surface functional groups. The ZnCl 2 activated carbon had the highest adsorption capacity for MTBE adsorption, followed by H 3 PO 4 and KOH activated carbons. The results showed that the highest MTBE removal was observed at solution pH equal to 4 and approximately 30% of MTBE could be adsorbed with 30 min contact time. It was also found that MTBE adsorption followed the R–P isotherm and pseudo-second order (type 1) kinetic models. During ANN modeling, the optimum neurons number for Levenberg–Marquardt training algorithm was determined equal to 5 with highest R 2 value and lowest mean square error were found to be 0.99 and 5.7 × 10 –4 , respectively.