Treatment of petroleum refinery wastewater by an innovative electro-Fenton system: Performance and specific energy consumption evaluation

Abstract

The study successfully applied an effective method for removing chemical oxygen demand (COD) from Iraqi petroleum refinery wastewater (PRW) using electro-Fenton (EF) with a new design of electrochemical reactor equipping with a novel cathode design. The study examined the effects of the primary operational parameters, including current density, Fe2+ concentration, and time, on the removal of COD using response surface methodology (RSM). The optimum operating conditions to maximize the COD removal (RE%) and minimize the specific energy consumption (SEC) were found to be a current density of 10.4545 mA/cm2, Fe2+ concentration of 0.50 mM, and a reaction time of 57.57 min, resulting in a RE% of 91.64% with SEC of 5.96 KW h/Kg COD. The study found that the current density had the main impact on RE% followed by Fe2+ concentration and reaction time. The R2 value was (98.53%) demonstrated the successful application of RSM in PRW treatment. The results suggest that the EF process with MPGADC is a promising technology for post-treatment of PRW before final discharge into surrounding water bodies.