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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Photocatalytic wastewater treatment,Spent Caustic wastewater,Titanium dioxide,Artificial neural networks(ANN),Design of experiment (DOE)
- چکیده:
- چکیده انگلیسی: In this study, the photocatalytic method was used for treating the spent caustic in the wastewater of Olefin units used in petrochemical industries which contain large amounts of total dissolved solids (TDS). By using the synthetic photocatalyst of suspended titanium dioxide and measuring the chemical oxygen demand (COD) which was reduced in the photocatalyst (lbc) process, the values of COD were modeled and evaluated by means of the Box-Behnken (BBD) and the artificial neural network (ANN) using experimental tests in a double-cylindrical-shell photo reactor. According to the applied calculations, it was found that the artificial neural network was a more suitable method than the experimental design in modeling and forecasting the amount of COD removal. The modeling employed in this research showed that increasing the concentration of the photocatalyst in a state of neutral pH enhanced the COD removal up to the optimal amount of 1.31 g/L without restrictions and 2 g/L with restrictions at the rate of 81% and 79%, respectively. In addition, the study of the parameter effects including oxidizer amount, aeration rate, pH, and the amount of loaded catalyst indicated that all factors except pH had a positive effect on the model; furthermore, if the interactions were neglected, the COD removal efficiency would increase by increasing each of these factors (except pH). In addition, there was no interaction between the aeration and the concentration of the photocatalyst, and the acidic pH was more suitable at low concentrations of the photocatalyst. Besides that, by increasing the pH, the efficiency of removal was reduced when the oxidant was at its low level. The results showed that photolysis and adsorption adoptions had a very small effect on the efficiency of the removal of COD compared to the photocatalyst adoptions, and it was insignificant. In addition, the photocatalytic method had an acceptable capacity for removing the phenol in the wastewater sample, whereas it was inefficient in reducing the sulfide solution in the wastewater.
- انتشار مقاله: 23-03-1394
- نویسندگان: Aَli Haghighi Asl,Amin Ahmadpour,Narges Fallah
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: TiO2/Fe3O4 and TiO2/Fe2O3 nanocomposites,Ultrasonic-assisted deposition-precipitation method,Photocatalytic activity,Methyl orange
- چکیده:
- چکیده انگلیسی: Environmental contamination, which is growing around the world, is a serious problem can not to be neglected. Among all contaminations, water pollution is a major problem. Azo dyes are one of the largest groups of pollutants found in the drinking water, coming from, and the food and textile industries. TiO2/Fe3O4 and TiO2/Fe2O3 nanocomposites with various ratios were synthesized by an ultrasonic-assisted deposition-precipitation method and their UV-light decolorization of methyl orange (MO) dye was investigated. The effect of Fe3O4/TiO2 and Fe2O3-TiO2 nanocomposites ratio on the photocatalytic activity and magnetic property of the nanocomposites was studied by comparing their decolorization curves and magnetism in the presence of magnet, respectively. The results revealed that the decolorization efficiency of 1 wt% Fe3O4/TiO2 nanocomposite reached about 40% within 60 min UV irradiation at room temperature. However, this sample showed the least magnetism. Also, the ability of synthesized nanocomposites in holding the adsorbed methyl orange dye on their surface and the effect of pH were investigated.
- انتشار مقاله: 04-12-1394
- نویسندگان: Amin Ahmadpour,Amin Ahmadpour,Amin Ahmadpour
- مشاهده