On the Limitation of Fenton Oxidation Operational Parameters: A Review

Abstract

Abstract The literature on the use of Fenton oxidation in wastewater treatment has established the method as one of the most effective and suitable methods for recalcitrant wastewater treatment. It is an advanced oxidation process (AOP) that utilises the highly reactive hydroxyl radical (•OH) to aggressively and non-selectively destroy organic contaminants. The Fenton oxidation possesses environmental and economic benefits coupled with effective mineralisation of most wastewater organics. Broadly, the Fenton oxidation encompasses three types of oxidation routes for the production of •OH: (i) through the use of Fenton reagents alone, termed classical Fenton oxidation (CFO), (ii) assisted by means of UV (photo-Fenton), or (iii) electron beams (electro-Fenton). However, this review is limited to CFO, which involves the catalytic decomposition of hydrogen peroxide (H2O2) by suitable transition metals to generate •OH. Despite the many advantages of the CFO process, there are issues related to operational parameters and the final treated wastewater, the most notable being pH modulation, the presence of the catalyst and the cost of the oxidant (H2O2). Furthermore, sludge generation constitutes an apparent drawback to the utilisation of this technology. This paper attempts to review the highlighted limitations and presents researches and advances reported in the literature addressing these issues.