Experimental Design of Photo-Fenton Reactions for the Treatment of Car Wash Wastewater Effluents by Response Surface Methodological Analysis

Abstract

Establishing a treatment process for practical and economic disposal of car wash wastewater has become an urgent environmental concern. Photo-Fenton's process as one of the advanced oxidation processes is a potentially useful oxidation process in treating such wastewater. Lab-scale experiments with UV source, coupled with Fenton's reagent, showed that hydrocarbon oil is degradable through such a process. The feasibility of photo-Fenton's process to treat wastewater from a car wash is investigated in the present study. A factorial design based on the response surface methodology was applied to optimize the photo-Fenton oxidation process conditions using chemical oxygen demand (COD) reduction as the target parameter to optimize. The reagent (Fe 2+ and H 2 O 2 concentration) and pH are used as the controlling factors to be optimized. Maximal COD reduction (91.7%) was achieved when wastewater samples were treated at pH 3.5 in the presence of hydrogen peroxide and iron in amounts of 403.9 and 48.4 mg/L, respectively.

Modelling Dimethoate Removal by Fenton-Like Process Using Response Surface Methodology

“…Scavengingeffects of excess H2O2 concentration at initial H2O2 concentrations above 0.15 mM.Iron concentrations above the optimal value result in reduced process performance because more species of iron ions are produced rather than the more useful •OH radicals. This finding is in agreement with the previous observation of Tony and Bedri [25].…”

“…The observed stoichiometric ratio of Fe 3+ :H2O2 was 1:5. The experimental results agree with values reported in the literature [17,[25][26][27].…”

“…However, at higher peroxide concentrations, the excess hydrogen peroxide can act as an OH• scavenger [25]. Scavenging is recombination of hydroxyl radicals and also hydroxyl radicals reaction with H2O2, contributing to the OH• scavenging capacity (Equations (4)- (6)) [26].…”

“…Scavenging is recombination of hydroxyl radicals and also hydroxyl radicals reaction with H2O2, contributing to the OH• scavenging capacity (Equations (4)- (6)) [26]. At higher peroxide concentrations, H2O2 forms HO2•, which is also a free radical produced in situ from theH2O2 but is a less reactive oxidizing agent and therefore has a longer life time than the OH• and the overall reaction rate reduces [25].…”

Removal of Pb (II) Ions in The Aqueous Solution by Photo-Fenton Method

“…There is a homogeneous oxidation method that also provides ˙OH radicals called photo-Fenton. Katoch, 2016; Palanivelu, 2004, 2005;Huang et al, 2010;Kusi et al, 2006;Tony and Bedri, 2014;Zazouli et al, 2012;Azhdarpoor et al, 2015;Wahyuni et al, 2016;Shaban et al, 2017;Çiner, 2017;Ali and Ameta, 2013). In this process, H2O2 is decomposed catalytically by Fe 2+ at acidic pH, yielding hydroxide ion (OH − ) and hydroxyl radical (˙OH) (reaction 4).…”