Microwave-Assisted COD Removal from Landfill Leachate by Hydrogen Peroxide, Peroxymonosulfate and Persulfate

H₂O₂-based advanced oxidation processes (AOPs) and SO₄^·--based AOPs were proved novel and promising techniques in treatment of wasterwater. Microwave (MW)-assisted hydrogen peroxide (H₂O₂), peroxymonosulfate (PMS) and persulfate (PS) were used to dispose of COD in landfill leachate. Oxidant dosage and chloride concentration were investigated as the major operating conditions. The initial COD is 4062.8 mg/L. It is demonstrated that MW-assisted H₂O₂, PMS and PS can effectively degrade leachate organics, and the COD removal can reach 43.5%, 80.2%, 97.3% when the oxidant concentration is 0.3 mol/L, respectively. Chloride ion will slightly improve the reaction rate for H₂O₂ and PS, while a little slow down for PMS, but all the eventual COD removal efficiencies keep stable. Generally speaking, MW-assisted peroxide is a powerful means in degradation of COD in landfill leachate.