Post-treatment of palm oil mill effluent (POME) using combined persulphate with hydrogen peroxide (S2O82-/H2O2) oxidation

Abstract

The aim of the current study is to evaluate the effectiveness of combined persulphate with hydrogen peroxide (S₂O₈^2-/H₂O₂) oxidation as a post-treatment of biologically treated palm oil mill effluent (POME) for the first time in the literature. The removal efficiencies of chemical oxygen demand (COD), ammoniacal nitrogen (NH₃-N), and suspended solids (SS) were 36.8%, 47.6%, and 90.6%, respectively, by S₂O₈^2- oxidation alone under certain operation conditions (i.e., S₂O₈^2- = 0.82 g, pH 11, and contact time 20 min). Nevertheless, the combined process (S₂O₈^2-/H₂O₂) achieved 75.8% and 87.1% removals of NH₃-N and SS, respectively, under 2.45/1.63 g/g H₂O₂/S₂O₈^2-, pH 11, and 20 min oxidation. Moreover, 56.9% of COD was removed at pH 8.4.