Abstract
Solid acid MoO3/ZrO2-TiO2 catalysts were prepared by impregnation method, and catalytic hydrolysis of difluorodichloromethane(CFC-12) over the catalyst was studied. The presence of MoO3/ZrO2-TiO2 catalyst in polycrystalline state could be clearly observed by transmission electron microscopy (TEM). Mesopores were detected by N2 adsorption-desorption isotherms which further confirmed the MoO3/ZrO2-TiO2 structural characteristics of catalyst. The results of NH3-TPD showed that the calcination temperatures had a great influence on the acidity of the catalyst, and the weak acidic site had a strong catalytic activity for the catalytic hydrolysis of CFC-12. Moreover, ZrO2-TiO2 was highly dispersed in the MoO3 framework, suggested by powder X-ray diffraction (XRD) and N2 adsorption-desorption results. The effects of the catalyst calcination temperatures on the conversion rate of CFC-12 were studied. The effects of catalytic hydrolysis temperatures and water vapor concentration on the catalytic hydrolysis rate of CFC-12 were also studied. The solid acid MoO3/ZrO2-TiO2 was calcined at 500 °C for 3 h at a catalytic hydrolysis temperature of 400 °C and water vapor concentration of 83.18%, and catalytic hydrolysis rate of CFC-12 reached 98.65 %. The hydrolysis rate of CFC-12 remained above 65.34% after 30 hours continuous reaction.
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References
Molina M J, Rowland F S. Stratospheric Sink for Chlorofluoromethanes: Chlorine Atom-catalysed Destruction of Ozone[J]. Nature, 1974, 249: 810–812
Roland F S, Molina M J. Ozone Depletion-20 Years after the Alarm[J]. Chem. Eng. News., 1994, 72: 8–13
Gammie F. Breakaway Iceberg’ due to Warming’[J]. Nature International Weekly Journal of Science, 1995, 374: 108
Guo H D, Yue Z, Chang L L, et al. Decomposition of Gaseous CF2Cl-Br by Cold Plasma Method[J]. J. Environ. Sci., 1997, 9: 11–19
Liu Z, Pan X, Dong W, et al. Decomposition of CF3Cl by Corona Discharge[J]. J. Environ. Sci., 1997: 95–99
Gal A, Ogata A, Futamura S, et al. Mechanism of the Dissociation of Chlorofluorocarbons during Nonthermal Plasma Processing in Nitrogen at Atmospheric Pressure[J]. The Journal of Physical Chemistry A, 2003, 107: 8 859–8 866
Ya F W, Wen J L, Chuh Y C, et al. Decomposition of CFC-12 by Adding Hydrogen in a Cold Plasma System[J]. Environ. Sci. Technol., 1999, 33: 2234–2240
Liu T C, Ning P, Wang H B, et al. Catalytic Decomposition of CFC-12 over Solid Super Acid MoO3/ZrO2[J]. Asian J. Chem., 2010, 22: 4 431–4 438
Liu T C, Guo Y J, Ning P, et al. Kinetics Study on Catalytic Hydrolysis of CCl2F2 over Solid Acid MoO3/ZrO2[J]. Advanced Materials Research, 2013, 750–752: 1 283–1 286
Hua W M, Zhang F, Ma Z, et al. WO3/ZrO2 Strong Acid as a Catalyst for the Decomposition of Chlorofluorocarbon (CFC-12)[J]. Chem. Res. Chinese U, 2000, 16: 185–187
Takita Y, Moriyama J I, Yoshinaga Y, et al. Adsorption of Water Vapor on the AlPO4- Based Catalysts and Reaction Mechanism for CFCs Decomposition[J]. Appl. Catal. A. Gen., 2004, 271: 55–60
Ma Z, Hua W M, Tang Y, et al. Catalytic Decomposition of CFC-12 over Solid Acids WO3/MxOy (M=Ti, Sn, Fe)[J]. J. Mol. Catal. A Chem., 2000, 159: 335–345
Zhang H X, Ching F N, SukY L. Catalytic Decomposition of Chloro-difluoromethane (HCFC-22) over Platinum Supported on TiO2-ZrO2 Mixed Oxides[J]. Appl. Catal. B. Environ., 2005, 55: 301–307
Navio J A, Macías M, Colón G, et al. Combined Use of XPS, IR and EDAX Techniques for the Characterization of ZrO2-SiO2 Powders Prepared by a Sol-gel Process[J]. Appl. Surf. Sci., 1994, 81: 325–329
Devotta S, Waghmare A V, Sawant N N. Alternatives to HCFC-22 for Air Conditioners[J]. Appl. Therm. Eng., 2001, 21: 703–715
Zuiderweg A, Kaiser J, Laube J C. Stable Carbon Isotope Fractionation in the UV Photolysis of CFC-11 and CFC-12[J]. Atmos. Chem. Phys., 2012, 12: 4 379–4 385
Suk Y L, Zhang H X, Ching F N. Deactivation of Gold Catalysts Supported on Sulfated TiO2-ZrO2 Mixed Oxides for CO Oxidation during Catalytic Decomposition of Chlorodifluoromethane (HCFC-22)[J]. Catal lett., 2004, 92: 107–114
Wang I, Chang W F, Shiau R J. Nonoxidative Dehydrogenation of Ethylbenzene over TiO2-ZrO2 Catalysts: I. Effect of Composition on Surface Properties and Catalytic Activities[J]. J. Catal., 1983, 83: 428–436
Vishwanathan V, Roh H S, Kim J W, et al. Surface Properties and Catalytic Activity of TiO2-ZrO2 Mixed Oxides in Dehydration of Methanol to Dimethyl Ether[J]. Catal. Lett., 2004, 96: 23–28
Ma Z, Hua W M, Tang Y, et al. Catalytic Decomposition of CFC-12 over WO3/TiO2[J]. Chem. Lett., 1999, 1 215–1 216
Chary K V R, Bhaskar T K, Gurram R, et al. Characterization and Reactivity of Molybdenum Oxide Catalysts Supported on Niobia[J]. J. Phy. Chem. B, 2001, 19: 4 392–4 399
Acknowledgement
Yunnan Minzu University is gratefully acknowledged for providing us with the facilities for the XRD and BET study. At the same time, I would like to thank Tong Zhou, Zhiqian Li, Guoqing Ren for their help with the expriment and Professor Tiancheng Liu guidance to the experiment.
Funding
Funded by the National Natural Science Foundation of China (No.51568068), and the Young and Middle-aged Academic and Technical Leaders Reserve Talent Program (No.202105AC160054)
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Tan, X., Zhou, T., Li, Z. et al. Catalytic Hydrolysis of CFC-12 over MoO3/ZrO2-TiO2. J. Wuhan Univ. Technol.-Mat. Sci. Edit. 38, 59–64 (2023). https://doi.org/10.1007/s11595-023-2667-y
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DOI: https://doi.org/10.1007/s11595-023-2667-y