| Abstract: | In this study,Co/Zr-metal organic framework(MOF)precursors were obtained by a room-temperature liquid-phase precipitation method and the equivalent-volume impregnation method,respectively,using a Zr-MOF as the support,and Co/Zr-MOF-M and Co/Zr-MOF-N catalysts were prepared after calcination in a hydrogen-argon mixture gases(VAr∶ VH2=9∶ 1)at 350℃for 2 h.The catalytic activities of the prepared samples for CO2 methanation under atmospheric-pressure cold plasma were studied.The results showed that Co/Zr-MOF-M had a good synergistic effect with cold plasma.At a discharge power of 13.0 W,VH2∶ VCO2=4∶:1 and a gas flow rate of 30 ml·min-1,the CO2 conversion was 58.9％and the CH4 selectivity reached 94.7％,which was higher than for Co/Zr-MOF-N under plasma(CO2 conversion 24.8％,CH4 selectivity 9.8％).X-ray diffraction,scanning electron microscopy,transmission electron microscopy,N2 adsorption and desorption(Brunauer-Emmett-Teller)and x-ray photoelectron spectroscopy analysis results showed that Co/Zr-MOF-M and Co/Zr-MOF-N retained a good Zr-MOF framework structure,and the Co oxide was uniformly dispersed on the surface of the Zr-MOF.Compared with Co/Zr-MOF-N,the Co/Zr-MOF-M catalyst has a larger specific surface area and higher Co2+/Cototal and Co/Zr ratios.Additionally,the Co oxide in Co/Zr-MOF-M is distributed on the surface of the Zr-MOF in the form of porous particles,which may be the main reason why the catalytic activity of Co/Zr-MOF-M is higher than that of Co/Zr-MOF-N. |
