Zahra Mirkazehi; Mohammad Reza Rezaei; Mohammad Sayadi
Abstract
Landfill leachate is the fluid percolating through the landfill and is one of the most important environmental challenges that lead to the contamination of water and soil resources. In this study, magnetic graphene oxide nanoparticles with WO3 (GO-Fe3O4/WO3) were synthesized through the hydrothermal ...
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Landfill leachate is the fluid percolating through the landfill and is one of the most important environmental challenges that lead to the contamination of water and soil resources. In this study, magnetic graphene oxide nanoparticles with WO3 (GO-Fe3O4/WO3) were synthesized through the hydrothermal method to eliminate chemical oxygen demand (COD) from leachate. The obtained products were characterized using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric analysis (TGA), and Vibrating sample magnetometer (VSM) analysis. The influence of various operating parameters, such as initial solution pH, adsorbent dosage, contact time, and temperature, on COD removal was studied. Additionally, kinetic, isotherm, and thermodynamic studies were conducted to evaluate the adsorption capacity of the adsorbent. The results revealed that the maximum adsorption capacity of GO-Fe3O4/WO3 was 2500 mg/g adsorbent at pH 4, a contact time of 90 minutes, an adsorbent dosage of 25 mg g-1, and a temperature below 298 K, respectively. According to the adsorption kinetic fitting results, the experimental adsorption data were well described by the pseudo-second order kinetic with an R2 value of 0.97, and the Freundlich isotherm equation with an R2 value of 0.99. The thermodynamic results indicated that the adsorption was spontaneous and exothermic for COD adsorption. In general, the adsorption process of the synthesized GO-Fe3O4/WO3 nanocomposite revealed that it is highly effective for landfill leachate treatment and has great practical value in leachate treatment.
Maryam Adimi; Maziar mohammadpour; Hassan Fathinejadjirandehi
Abstract
This research reported a study on COD removal from petrochemical wastewater (ml/l) by the electro-Fenton process via the effects of different parameters such as reaction time, current density, pH, H2O2/Fe2+ molar ratio, and volume fraction of H2O2. For this purpose, first, the Nanopores on the aluminum ...
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This research reported a study on COD removal from petrochemical wastewater (ml/l) by the electro-Fenton process via the effects of different parameters such as reaction time, current density, pH, H2O2/Fe2+ molar ratio, and volume fraction of H2O2. For this purpose, first, the Nanopores on the aluminum electrode surface were prepared as the AAO films were fabricated using the two-step anodization of 6063 aluminum alloy sheets at ambient temperature in sulfuric acid and phosphoric acid electrolyte solutions respectively.The nanostructures created on electrode confirmed by Scanning Electron Microscopy (SEM). Then, Efficiency of electrochemical oxidation process was tested by COD determination via electrolyte cell contain waste water, Fe2+, H2O2 and AAO electrode based on experimental design. The optimum COD removal (65.03%) was obtained at pH of 2.96, the reaction time of 89.51 min, the current density of 69.57 mA, the H2O2/Fe2+ molar ratio of 3.42 and volume fraction of H2O2 to petrochemical wastewater of 1.93 (ml/l).