Catalytic oxidation of organic pollutants
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The paper presents the results of the measurements of the catalytic activity of V2O5/TiO2 and MoO3/TiO2 catalysts (8,10,12 and 15 wt % of V2O5 or MoO3 on TiO2 - anatase, respectively), prepared in our laboratory, in the complete oxidation (combustion) process of chosen volatile organic pollutants of the air such as methanol and n-butyl acetate. The activity of these catalysts was compared with the activity of industrial catalysts: supported platinum - Pt-p (0.15 wt % of Pt on γ-Al2O3) and MCA (15 wt % of CuO and 6 wt % of ZnO on γ-Al2O3). The investigations were carried out in the kinetic region (powder of the catalysts with the diameter in the range of 1.02-1.2·10-4 m) and for the chosen catalysts also in the diffusion region (the grains of the catalysts having the diameter of 2.5·10-3 m). On the basis of the obtained results the analysis of the process was performed.It has been stated that reaction rate is well-described by the first order equation in relation to the methanol or n-butyl acetate concentration. On the basis of the obtained results in the kinetic region for all the applied catalysts the parameters of Arrhenius equation were determinated.The comparison of the results for the kinetic region with the results for the diffusion region for the chosen catalysts allowed the calculation of the effective coefficients of diffusion. The parameters of Arrhenius equations as well as the effective coefficients of diffusion show a good correlation with the values obtained for the catalytic combustion of other organic pollutants of the air.The measurements were carried out using a flow tubular reactor. The flow rate of the reaction mixture was kept constant 20 dm3/h (5.56·10-6 m3/s) in each test, using the space velocity of 20 s-1. It has been stated that the use of the applied catalysts led to the almost total oxidative destruction of both pollutants. Only H2O and CO2 were found as the final products of the reaction. The complete oxidation of the methanol process runs at the lower temperature than that of the complete oxidation process of n-butyl acetate. The most active at the combustion of methanol was the Pt-p catalyst. It demonstrates a comparable activity to molybdenum - titanium catalysts and the slightly lower activity than vanadium - titanium catalysts in the combustion of the n- butyl acetate process. The MCA catalyst was less active than the others in the oxidation of both compounds. The structures of the catalysts were tested using the X -ray analysis (XRD), infrared spectroscopy and scanning microscopy (SEM).The results of the investigations show that V2O5/TiO2 and MoO3/TiO2 catalysts, especially the most active of them the 8% V2O5/TiO2 catalyst can be used in industrial systems for the purification of the air and industrial waste gases with VOCs, replacing the more expensive noble metals supported catalysts.
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- Konieczyński, J. (1993). Oczyszczanie gazów odlotowych, Published by Silesian Technical University, Gliwice, Poland.
- Wojciechowski, J. (1992). Oczyszczanie gazów metodą Swingtherm-doświadczenia z 10 lat eksploatacji, Przemysł Chemiczny, 71 (6), 230-232.
- Avgourpoulos, G., Oikonomopoulos E., Kanistras D. & Ioannides, T. (2006). Applied Catalysis B: Environmental, Complete oxidation of ethanol over alkali-promoted Pt/Al2O3 catalysts, 65, 62-69. DOI: 10.1016/j.apcatb.2005.12.016[Crossref]
- Tsou, J., Magnoux P., Guisnet M., Órfao, J. J. M. & Figueiredo, J. L. (2005). Catalytic oxidation of volatile organic compounds. Oxidation of methyl-isobutyl-ketone over Pt/zeolite catalysts.Applied Catalysis B: Environmental, 57, 117-123. DOI: 10.1016/j. apcatb.2004.10.013.[Crossref]
- Baker, J. E., Burch R. & Golunski S. E. (1989). Thermal Analysis of catalyst surfaces.Termochimica Acta, 142 (2), 329-342. DOI:10.1016/0040-6031(89)85029-4.[Crossref]
- Nowicki, B. & Masiarz, A. (1995). Badania nowych katalizatorów platynowych do oczyszczania gazów z zanieczyszczeń organicznych i tlenku węgla.Przemysł Chemiczny, 74 (3), 100-102.
- Agarwal, S. K., Spivey, J. & Butt, J. B. (1992). Deep oxidation of hydrocarbons, Applied Catalysis A: General, 81(2), 239-255. DOI: 10.1016/0962-860X(92)80096-U.[Crossref]
- Straszko, J., Szpilski, W. & Kalisiak, B. (1994). Katalizatory procesu spalania toksycznych domieszek powietrza.Przemysł Chemiczny, 73 (5), 176-178.
- Nowicki, J. & Masiarz, A. (1992). Badania aktywności krajowych katalizatorów tlenkowych w procesie utleniania tlenku węgla.Przemysł Chemiczny, 71 (9), 344-346.
- Spivey, J. J. (1987). Complete catalytic oxidation of volatile organics.Ind. Eng. Chem. Res., 27 (11), 2165-2180. DOI: 10.1021/ie00071a001.[Crossref]
- Wang, C.-H. (2004). Al2O3- supported transition-metal oxides for catalytic incineration of toluene.Chemosphere, 55 (1), 11-17. DOI: 10.1016/j.chemosphere.2003.10.036.[Crossref]
- Kennedy, L. A. & Ruckenstein, E. (1984). Catalytic combustion, Catalysis Reviews, 26 (1), 1-58. DOI: 10.1080/0161498408078059.[Crossref]
- Drago, R. S., Jurczyk, K., Singh, D. J. & Young, V. (1995). Low-temperature deep oxidation of hydrocarbons by metal oxides supported on carbonaceous materials.Applied Catalysis B: Environmental. 6, 155-168. DOI: 10.1016/0926-3373(95)00009-7.[Crossref]
- Matsuda, S. & Kato, A. (1983). Titanium oxide based catalysts - a review.Applied Catalysis B: Environmental. 8 (2), 149-165, DOI: 10.1016/0166-9834(83)80076-1.[Crossref]
- Kato, Y. (JP) & Konishi, K. (JP), (Babcock Hitachi KK, JP). (June 1993). Catalyst for purifying exhaust gas. EUROPEAN PATENT APPLICATION. Patno. EP0544282.
- Straszko, J. (1979). Modelowanie kinetyki procesów kontaktowych. Unpublished dissertation, Szczecin Univerisy of Technology, Poland.
- Szarawara, J. & Skrzypek, J. (1980). Podstawy inżynierii reaktorów chemicznych, WNT, Warszawa, Poland.
- Kaczanowska- Ławniczak, Z. (1982). Dyfuzja mieszanin w porowatych katalizatorach i sorbentach przemysłowych. Unpublished doctoral dissertation, Szczecin University of Technology, Poland.
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