Optimization of COD removal from leachate nanofiltration concentrate using H2O2/Fe+2/heat – Activated persulfate oxidation processes

This study aimed to remove COD from leachate nanofiltration concentrate (LNFC) by oxidation of H2O2/Fe2+/Heat - activated persulfate (PS) and optimization and modelling of its removal using a Central Composite Design (CCD) by the Response Surface Methodology (RSM). In the results of ANOVA where the experimental data of the study were analyzed, high correlation coefficients (R2 > 0.80) were obtained from all three processes, and it was seen that models could be explained by these data. The COD removal efficiencies under the optimum conditions for the H2O2, Fe2+ and Heat - activated PS processes were 56.9%, 76.2% and 93.5%, respectively. About 64.3%, 78% and 93.2% removal efficiency values of inert COD were obtained after the H2O2-activated PS, Fe2+-activated PS and Heat-activated PS processes, respectively. Consequently, the heat-activated PS process may be an alternative technology for COD and inert COD removal from leachate nanofiltration concentrate.