Biochar production from agricultural waste usinghydrothermal method, characterization and removalof pollutants from aqueous solutions

In this study, biochar produced from pea pods (PP), an agricultural waste, at different incineration temperatures (400, 500 and 600°C) was converted into magnetic biochar (MBC) by hydrothermal method using different iron additions (1:1, 2:1, 3:1 ratios) and then the effects of peroxymonosulfate (PMS) activation on Reactive Blue 19 dye removal were investigated. SEM-EDS, XRD, FTIR, VSM and BET analyses were performed to determine the characterization of the produced magnetic biochar and the catalyst was characterized. The effect of solution pH, MBK dosage, PMS concentration, initial dyestuff concentration, reusability, anion and natural organic matter concentrations on RB19 removal by PMS activation using magnetic biochar was investigated and parameters were optimized. In this study where the most effective parameters were determined, it was observed that 87% removal efficiency was obtained when iron addition was used at a ratio of 3:1, solution pH was 3, MBK dosage was 0,2 g/L and PMS dosage was 0,5 mM at an incineration temperature of 500°C. In the reusability experiments, it was determined that the removal efficiency of RB19 decreased from 87% to 79% when the produced material was used 4 times. Although there is some decrease in the removal efficiency in the fourth use, a level of 79% shows that the system works successfully and can be used in future studies. As a result of kinetic calculations, the Behnajady-Modirshahla-Ghanbery (BMG) kinetic model was found to be more effective to describe the removal efficiency of RB19.