Activated Carbon Assisted Fenton-like Treatment of Wastewater Containing Acid Red G

Abstract

The Fenton reaction as an effective advanced oxidation technology has been widely used in wastewater treatment for its stable effluent quality, simple operation, mild condition, and higher organic degradation with non-selectivity. However, the traditional Fenton reaction is limited by the sluggish regeneration of Fe2+, resulting in a slower reaction rate, and it is necessary to further increase the dosage of Fe2+, which will increase the production of iron sludge. Activated carbon (AC) has a strong adsorption property, and it cannot be ignored that it also can reduce Fe3+. In this study, the degradation of acid red G (ARG) by adding AC to the Fe3+/H2O2 system, the role of the reducing ability, and the reason why AC can reduce Fe3+ were studied. By adding three kinds of ACs, including coconut shell-activated carbon (CSPAC), wood-activated carbon (WPAC), and coal-activated carbon (CPAC), the ability of ACs to assist the Fe3+/H2O2 Fenton-like system to degrade ARG was clarified. Through the final treatment effect and the ability to reduce Fe3+, the type of AC with the best promotion effect was CSPAC. The different influence factors of particle size, the concentration of CSPAC, concentration of H2O2, concentration of Fe3+, and pH value were further observed. The best reaction conditions were determined as CSPAC powder with a particle size of 75 μm and dosage of 0.6 g/L, initial H2O2 concentration of 0.4 mmol/L, Fe3+ concentration of 0.1 mmol/L, and pH = 3. By reducing the adsorption effect of CSPAC, it was further observed that CSPAC could accelerate the early reaction rate of the degradation process of ARG by the Fe3+/H2O2 system. FT-IR and XPS confirmed that the C-O-H group on the surface of CSPAC could reduce Fe3+ to Fe2+. This study can improve the understanding and role of AC in the Fenton reaction, and further promote the application of the Fenton reaction in sewage treatment.

Fenton: A Systematic Review of Its Application in Wastewater Treatment

“…Regarding the treatment of wastewater with dyes, studies on this topic have increased in the last 10 years of the study period (2012-2022; r = 0.85 with time) [31][32][33]. Studies on the removal of organic compounds increased after 2015 (r = 0.87), showing that organic compounds were the most commonly used matrix in Fenton studies [34][35][36] in comparison with pharmaceuticals [37][38][39], phenols [40,41], pesticides [42,43], inorganic compounds [44,45], hygiene and cleaning products [46,47].…”

Optimal concentration and efficiency of the photo fenton system for the treatment of a synthetic textile effluent

“…One of the most effective AOPs for the generation of the hydroxyl radical is the Fenton process, based on Fe 2+ and H2O2, where the radicals are formed by catalytic decomposition of H2O2, with Fe 2+ being the catalyst (Cruz-Gonzalez et al, 2017) at low pH conditions (pH of 2-4) (Yan et al, 2022) (Equation 1). When H2O2 is combined with iron salts, the reaction is generated (Equations 1 and 2).…”