Sima Zamand; Hossein Alidadi; Abolfazl Naimabadi; Vahid Taghavimanesh
Abstract
Background and Aim: : Produced wastewater by various industries is a dangerous and considerable pollution resource for the environment. The presence of non-biodegradable dyes in effluents of dying industries is regarded as a major problem. The purpose of this study was to evaluate the efficiency of electro-fenton ...
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Background and Aim: : Produced wastewater by various industries is a dangerous and considerable pollution resource for the environment. The presence of non-biodegradable dyes in effluents of dying industries is regarded as a major problem. The purpose of this study was to evaluate the efficiency of electro-fenton process in dye removal from the wastewater of dying industries. Materials and methods: : In the present experimental study conducted in 2017, wastewater sampling was performed according to the Standard Methods for the Examination of Water and Wastewater. The samples were transferred to the electrochemical cell reactor and the effect of different parameters such as applied voltage, iron concentration, pH, and reaction time on dye removal efficiency were investigated. Results: According to the results, optimum conditions of Electro-Fenton process in dye removal was determined. Accordingly, in applied voltages of 25 and 35 V in 100 and more than 200 mg/L dye concentrations, , reaction time of 50 - 60 minutes, Fe2+ concentration of 0.3 mg/L and pH of 3 the dye removal efficiency of 99.8 % was achieved. Conclusion: The electro-fenton process is able to remove dye with different concentrations and maximum efficiency. Based on the results, the applied voltage and the concentration of Fe2+ were the parameters that are more efficient and pH along with reaction time demonstrated less impact on the efficiency of the electro-fenton process in dye removal from industrial wastewater.
ghorban asgari; Javad Faradmal; Abdolmotaleb Seid-mohammadi; Halime Almasi; somaye akbari
Abstract
Background and objective: Industrialization has led not only to an increase in water demand, but also to an increase in water pollution due to the discharge of polluted industrial wastewaters with high salt content, and the organic compounds such as phenol into the water bodies. This ...
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Background and objective: Industrialization has led not only to an increase in water demand, but also to an increase in water pollution due to the discharge of polluted industrial wastewaters with high salt content, and the organic compounds such as phenol into the water bodies. This study aimed to investigate the efficiency of electrocuagulation and electro-Fenton processes in phenol removal from saline wastewater using Taguchi exprimental design method. Material and methods: This experimental study was performed in a reactor (1 liter) with synthetic phenolic saline wastewater. In this study for electrocoagulation process, the effects of five operation parameters on phenol removal efficiency including reaction time (20-80 min), electrolyte (1-4%), pH (3-5-7-9), initial phenol concentration (500-1000-1500-250 mg/L) and current density (4-16 mA/cm2) were investigated in four levels by Taguchi L16 orthogonal array. Also for electro-Fenton process, the effects of six operation parameters on removal efficiency in five levels including reaction time (20-80 min), electrolyte (0-4%), pH (2-3-4-6-8), initial phenol concentration (250-500-1000-1500-2000), current density ( 0-16mA/cm2) and hydrogen peroxide (50-300mg/L) were evaluated by Taguchi L25 orthogonal array. The concentration of phenol was determined according to the estandard method in spectrophotometric wavelength of 500 nm. Results: Experimental data showed that the optimum phenol elimination condition in electrocuagulation process was initial phenol concentration of 250 mg/L, pH = 5, electrolyt = 3%, curent density of 8 mA/cm2 and reaction time of 60 min. The most influential factor in removal efficiency was the initial concentration (63.2%), and the lowest effect belonged to the electrolyt (4.2%). The optimum phenol removal condition for electro-Fenton process was initial concentration of 250 mg/L, pH:3, electrolyt:2%, hydrogen peroxide:150 mg/L, current density of 8 mA/cm2 and 20 mine contact time. The most influential factor in elimination efficiency was the curent density (29.12%), and the lowest influence on response variable belonged to the reaction time (3.08%). Conclusion: This study showed the electro-Fenton process was effective in the removal of phenolthat can be used as an appropriate process in wastewater treatment.