Work

Treatment of petroleum refinery wastewater by a heterogeneous electro-Fenton process using activated carbon loaded with Fe2O3-CeO2 as a catalyst

Year: 2025

Type: article

Abstract: • A novel heterogeneous electro-Fenton system was successfully used to remove COD. • Catalyst dosage had the main effect on COD removal, followed by pH and current density. • 88.92% of COD was removed at 10.96 mA/cm 2 , pH 5, 0.76 g/L catalyst dosage, and 120 min. • Quenching experiments showed that ⦁ OH is the dominant oxidizing agent in the HEF. • HEF catalyst has recyclability and stability with good performance up to five cycles. The removal of chemical oxygen demand (COD) from a petroleum refinery wastewater (PRW) by heterogeneous electro-Fenton (HEF) was investigated using activate carbon (AC) loaded with iron and cerium as a HEF catalyst. The influence of HEF parameters including current density, pH, and catalyst dosage on the COD removal efficiency was studied and optimized using a response surface methodology (RSM). The results showed that the best COD removal of 88.92% was achieved at 10.96 mA/cm 2 , pH 5, 0.76 g/L catalyst dosage, and 120 min, with a claimed total electrical energy consumption (EEC) of 3.43 kWh/m 3 . The results confirmed that the catalyst dosage had the main effect on the COD removal, followed by the pH and current density. In addition, most terms of RSM models were statistically significant, and the model has a p-value of 0.0005 with R 2 equal to 98.95%. Quenching experiments showed that hydroxyl radicals ( ⦁ OH) are the dominant oxidizing agents in the HEF reactions. Furthermore, the degradation of COD was found to follow pseudo-first-order kinetics. The results confirmed the recyclability and stability of AC loaded with iron and cerium over five cycles. The synergistic effect of combining Ce with Fe on AC makes the present HEF catalyst a promising catalyst for treating complex wastewaters such as petroleum refinery effluent using HEF technology.

Source: Results in Engineering

DOI: 10.1016/j.rineng.2025.108249

Authors: Asyah R. Flayyih, Ali H. Abbar

Institution: University of Baghdad

Language: English

Topic: Advanced oxidation water treatment

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Clean water and sanitation, Responsible consumption and production, Affordable and clean energy

Open Access status: gold

Estimated APC paid: $1,940