Optimization of the Ultrasonic-Electroproxone Process Via Graphene-Titanium Electrodes in Removal of 2, 4 D from Synthetic Wastewater by RSM

Background: Advanced Hybrid Oxidation Processes(AHOPs) have the ability to romove the pesticides. The aim of this study was optimization of sono-electroperoxone process (US-EP) in the removl of 2.4 D from aqueous via RSM. Methods: The pilot that used to in this study included an ozone generator, an ultrasonic generator and an electric direct current source. Two graphene electrodes as  anodes and two titanium electrodes as cathodes were used. This electrodes connected to DC as direct monopolar connection. pH, direct electric current, ozone gas concentration, reaction time and initial 2,4 D concentration were optimized as  an independet and inffluence parameters. COD and TOC removal, kinetics of reaction, synergyist effects of variables, presence of radical scavangers and optimal electrolyte concentration were determined in optimum condition. Results: Efficiency of process was 55-90 percent in different runs. The optimized conditions are modeled was pH=6/04, ozone concentration equal to 2 mg/L.min, electric current equal to 1 amperes, 2, 4 D concentration equal to 30.3 mg/L and in 103 minutes reaction time in the presence of ultrasonic waves with frequencies 40 kHz. The Efficiency of US-EP in this situation was 95 percent. COD and TOC removal were 71% and 63%, respectively. The kinetics of the process follow the first order kinetics. The P-Value and F-value was determined by ANOVA analysis 0.0033 and 24.19 respectively, which indicates the model is significant. R2, R2 adj and R2 predicted were 0.94, 0.84 and 0.89, respectively. Conclusion: US-EP process had a high performance in removing of 2.4 D. The process is an environmentally friendly process because don’t use of chemicals.