Fluidized-bed Fenton process as alternative wastewater treatment technology—A review

Abstract

The manufacture of products for the growing population results in large volume of wastewater that needs treatment. Advanced oxidation processes (AOPs) are popular for low cost, high efficiency and being eco-friendly in the degradation of toxic pollutants in the wastewater using the generated non-selective hydroxyl radical (•OH) for oxidation. Among the many AOPs, the Fenton process has been proven to be effective for treating recalcitrant organic compounds by using Fe2+ and H2O2 to produce the •OH. One disadvantage is the production of a large amount of sludge that needs further treatment and disposal. The fluidized-bed Fenton (FBF) process uses carriers that reduce the production of sludge by crystallizing the target pollutant onto the carrier surface. This paper is a comprehensive review of the recent development on FBF process application to industrial wastewater treatment. FBF process was used to treat industrial wastewaters like thin film transistor liquid crystal display manufacturing effluents, pharmaceutical products, textile, phenol and phenol derivatives-containing wastewater and other refractory organics in wastewater. This review highlights the advantages of FBF process over other technologies that are based on Fenton oxidation in terms of performance, operating conditions and factors affecting the removal efficiency. Included in this review are the reaction kinetics and mechanism involved and the carriers that were used. Finally, full-scale applications are collected and described. This review has shown the potential applicability of FBF technology to reduce the levels of recalcitrant organic contaminants in wastewater effluents.