M. A. Kipnis, P. V. Samokhin, R. S. Galkin, E. A. Volnina, N. A. Zhilyaeva
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引用次数: 0
Abstract
The physicochemical and catalytic (CO2 hydrogenation) characteristics of Mo-containing catalysts were studied. The catalysts containing 8 and 15 wt % Mo oxide were prepared by impregnation of γ‑Al2O3 with ammonium paramolybdate, followed by drying and calcination at 500°C. The introduction of Mo oxide reduced the pore volume of the support and increased the average pore size, indicating that molybdenum oxide was distributed in the support pores. According to the X-ray diffraction analysis, the calcinated catalyst did not contain the crystalline MoO3 phase. According to the Raman spectra, oxygen-containing formations were present on the catalyst surface, with Mo atoms tetrahedrally and octahedrally coordinated to the oxygen atoms. The impregnated MoO3 was partially reduced with hydrogen during linear heating, starting from 320°C. The hydrogenation of CO2 (gas composition, vol %: 30.7 CO2, 68 H2, the rest was N2; 0.5 g sample) was studied under conditions of linear heating to 400°C. The main reaction was the reverse reaction of CO steam reforming. The contribution of methanation to CO2 hydrogenation was small. An increase in the temperature and pressure had a positive effect on CO2 conversion. When the pressure increased from 1 to 5 MPa, the CO content was approximately doubled. In the CO2 hydrogenation, appreciable activity (although significantly lower compared to that of Mo-containing catalysts) was also exhibited by γ-Al2O3, preliminarily heated to 400°C in an H2 flow. The activity of alumina also increased with pressure.
期刊介绍：
Kinetics and Catalysis Russian is a periodical that publishes theoretical and experimental works on homogeneous and heterogeneous kinetics and catalysis. Other topics include the mechanism and kinetics of noncatalytic processes in gaseous, liquid, and solid phases, quantum chemical calculations in kinetics and catalysis, methods of studying catalytic processes and catalysts, the chemistry of catalysts and adsorbent surfaces, the structure and physicochemical properties of catalysts, preparation and poisoning of catalysts, macrokinetics, and computer simulations in catalysis. The journal also publishes review articles on contemporary problems in kinetics and catalysis. The journal welcomes manuscripts from all countries in the English or Russian language.
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