Effectiveness of Solar Photo‐Fenton Process for Simultaneous Detoxification of Heavy Metals and Disinfection in Municipal Wastewater by Using Response Surface Method

Abstract

The goal of this paper was to evaluate the effectiveness of solar photo‐Fenton (Fe2+/H2O2/UV–vis) treatment that is able to degrade heavy metal contents (Cu, Cd, Cr, Fe, Ni, Pb and Zn) and pathogenic microbial population (Fecal Coliform/100 mL) present in municipal wastewater with minimal iron and H2O2 concentrations. Photo‐Fenton experiments were performed in a solar parabolic trough reactor (PTR). Three level factorial design and response surface method (RSM) was used for characterization and optimization of the process in which a response of interest is influenced by four key variables (pH, solar exposure time, catalyst dose (Fe2+/Fe3+), and amount of oxidant (H2O2)). The performance of advanced oxidant process was investigated in terms of percentage degradation of heavy metals and Fecal Coliform (FC) bacteria present in municipal wastewater. The result shows that variables have significant effect on the degradation process of municipal wastewater. Photocatalytic degradation efficiency was found to be dependent on optimized catalyst dose (Fe2+ 100 mg/L) and amount of oxidant (H2O2 500 mg/L). Analysis of variance (ANOVA) exhibited a high coefficient (R2 = 0.72–0.89), thereby indicating a satisfactory fit between the experimental results. The statistical model of solar photo‐Fenton has shown excellent performance. Excessive hydrogen peroxide and iron have shown scavenging effects on hydroxyl radicals and reduced degradation of micro‐pollutants present in wastewater. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 448–459, 2017