Photocatalytic Free Cyanid Elimination Process from the Industrial Wastewater Using a Synthesis Al2O3/TiO2 Catalyst

Document Type : Research Paper



The photocatalytic UV/TiO2 process has particular importance due to having high rate and efficiency in the removal of organic and inorganic contaminants from industrial wastewater. One of the problem of utilization of a catalyst with physical properties similar to TiO2 (anatase)  is the separation of the catalyst from the wastewater effluent. In this study, synthesis of titanium oxide on the surface of alumina (particle size 150 to 200 µm) with the wet impregnation method was accomplished in order to create a catalyst with suitable physical properties to easy separation capability from industrial effluents. Hence, titanium isoprpylate compound was used and after the reaction of alumina on the surface, in order to Synthesis of titanium oxide anatase form, calcinations being done in the temperature of 500 ◦C in an electric furnace. The amount of anatase phase formation was measured by X-ray diffraction technique. Finally the removal of free cyanide in the presence of TiO2 and Al2O3/TiO2 was investigated in optimal conditions with the Change of parameters such as irradiation time of UV, the amount of catalyst and initial concentration of cyanide. Experiments were carried out by using a batch photoreactor and a high pressure Hg lamp (250 watt). The results indicated that a layer of anatase TiO2 formed on the surface of Al2O3particles which its value depends on the increasing frequency synthesis. The study of the kinetic of


 cyanide removal process in the presence of the synthetic catalyst Al2O3/ TiO2 showed that the curve of concentration versus time is logarithmic in this process which indicated the reaction is the first order The results also showed that the catalyst TiO2 has a greater Photocatalytic activity in removal of cyanid compared to Al2O3/ TiO2 due to its higher purity and tiny particle size. However, the physical properties of Al2O3 /TiO2 catalyst including easy separation and reuse from industrial effluent in removal process, could justify economical and practical of its application.


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