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

Document Type : Research Paper

Authors

Abstract

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.

Keywords

References

1- Frank, S.N., and Bard, A.J. (1977).”Hetrogeneous photocatalytic oxidation of cyanide ion in aqueous solution at titanium dioxide powder.” J. of Am. Chem. Soc., 99, 303-304.
2- Duran, A., Monteagudo, J.M., San Martin, I., and Aguirre, M. (2010). “Decontamination of industrial cyanide-containing water in a solar CPC pilot plant.” J. of Solar Energy, 84, 1193-1200.
3- Marugan, J., Van Grieken, R., Cassano, A., and E., and Alfano, O.M. (2008). “Intrinsic kinetic modeling with explicit radiation absorption effects of the photocatalytic oxidation of cyanide with TiO2 and silica-supported TiO2 suspensions.” J. of Applied Catalysis B: Environmental, 85, 48-60.
4- Marugan, J., Grieken, R.V., Cassano, A.E., and Alfano, O.M. (2009). “Scaling-up of slurry reactors for the photocatalytic oxidation of cyanide with TiO2 and silica-supported TiO2 suspensions.” J. of Catalysis Today, 144, 87-93.
5- Aguado, J.R., Van Grieken, R.V., Lopez-Munoz, M.J., and Marugan, J. (2002). “Removal of cyanides in wastewater by supported TiO2-based photocatalysts.” J. of Catalysis Today, 75, 95-102.
6- Loddo, V., Marci, G., Martin, C., Palmisano, L., Rives, V., and Sclafani, A. (1999). “Preparation and characterization of TiO2 (anatase) supported on TiO2 (Rutile) catalysts employed for 4-nitrophenol photpdegradation in aqueous medium and compartion with TiO2 (anatase) supported on Al2O3.” J. of Applied Catalysis B: Environmental, 20, 29-45.
7- Addamo, M., Augugliaro, V., Di Paola, A., Garcia-Lopez, E., Loddo, V., Marci, G., Molinari, R., and Palmisano, L. (2004). “Preparation, characterization and photoactivity of polycrystalline nanostructured TiO2 catalysts.” J. of Phys. Chem., 108, 3303-3310.
8- Bellardita, M., Addamo, M., Di Paola, A., and Palmisano, L. (2007). “Photocatalytic behaviour of metal-loaded TiO2 aqueous dispersions and films.” J. of Chem. Phys., 339, 94-103.
9- Javier, M., Rafael, G., Alberto, E., and Orlando, M. (2008). “Intrinsic kinetic modeling with explicit radiation absorption effects of the photocatalytic oxidation of cyanide with TiO2 and silica-supported TiO2 suspensions.” J. of Applied Catalysis B: Environmental, 85, 48-60.
10- DeLos Reyes, J.A., Viveros, T., and Barrera, M.C. (2006). “Cyclohexane dehydrogenation over wet-impregnated Ni on Al2O3-TiO2 SolGel Oxides.” J. of Ind. Eng. Chem. Res., 45(16), 5693-5700.
11- Zhiming, Z., Tianying, Z., Zhenmin, C., and Yuan, W. (2011). “Preparation and characterization of titania-alumina mixed oxides with hierarchically macro-/mesoporous structures.” J. of Ind. Eng. Chem. Res., 50(2), 883-890.
12- Chiang, K., Amal, R., and Tran, T. (2003). “Photocatalytic oxidation of cyanide: Kinetic and mechanistic studies.” J. of Molecular Catalysis A: Chemical, 193, 285-297.
13- Andrew, D. (2005). Standard methods for examination of water and wastewater, 21th Ed., American Public Health Association, Washington, D.C.
14- Ghanbarian, M., Mahvi, A.H., Nabizadeh, R., and Saeedniya, S. (2008). “A pilot study of RO16 discoloration and mineralization in textile effluents using the nanophotocatalytic process.” J. of Water and Wastewater, 69, 45-51. (In Persian)
15- Movahedian Attar, H., and Rezaee, R. (2006). “Investigating the efficiency of advanced photochemical oxidation (APO) technology in degradation of direct azo dye by UV/H2O2 process.” J. of Water and Wastewater, 59, 75-83. (In Persian)
16- Movahedian Attar, H., Sid Mohammadi, A.M., and Assadi, A. (2009). “Comparison of different advanced oxidation processes degrading p-chlorophenol in aqueous solution.” Iranian J. of Environ. Health. Sci. Eng., 6(3), 153-160.
Journal of Water and Wastewater; Ab va Fazilab ( in persian )
Volume 24, Issue 3 - Serial Number 3
Serial number:87
September and October 2013
Pages 63-70

Files

Share

How to cite

Statistics