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In order to investigate catalytic performance of bio-char on microwave-assisted CH4/CO2 reforming, different bio-chars were obtained through change of biomass material, adjustment of char-making temperature, and deashing of raw materials. And then various bio-chars were served as catalysts for CH4 reforming reaction in a fixed bed reactor,to study catalytic effect of different bio-chars on the conversions of reactant gases. The results show that the metal oxide contained in bio-char can not only impose catalytic effect on CH4/CO2 reforming, but also can affect the response of bio-char to microwave. As a result,the metal oxide content in bio-char is determinant for its catalytic activity. The conclusion reached above was confirmed by the catalytic effect of deliming bio-char on CH4/CO2 reforming. In addition, the surface area and pore characteristics of bio-char also play a role in the catalytic performance of bio-char. Bio-char was mixed evenly with different additives to examine the influence of additives on bio-char catalytic properties. The results reveal that the bio-chars mixed with Na2CO3 or K2CO3 can bring an increase in CO2 conversion as well as a decrease in CH4 conversion. An improvement in catalytic performance of char was observed because of the introduction of MgO,CaO oi NiO. Finally,the addition of SiO2 was demonstrated to be unfavorable for the reforming reaction. [ABSTRACT FROM AUTHOR]

High-grade syngas can be produced from the reforming of CH4 with CO2. To achieve efficient conversion of reforming reaction into syngas production, the reforming of CH4 with CO2 for syngas production was conducted in this paper under microwave irradiation, with biomass char as catalyst and microwave absorbing medium. The influences of the conditions including reaction temperature, molar ratio of CO2 and CH4, addition amount of biomass char as well as the introduction of water vapor on the reforming reaction were investigated. The results reveal that an increase in the conversion of reactant gases into syngas production can be achieved through raising reaction temperature, enhancing molar ratio of CO2 and CH4 or increasing addition amount of biomass char. Raising reaction temperature results in a promotion in the ratio of H2 to CO, while enhancing molar ratio of CO2 to CH4 or increasing addition amount of biomass char bring about a decrease in the ratio of H2 to CO. And the introduction of water vapor is not only favorable for the reforming reaction, but also is responsible for an increase in the ratio of H4 to CO. [ABSTRACT FROM AUTHOR]

The microwave-assisted heating apparatus was employed to study the reforming of CH4 with CO2 over activated carbon. The influences of microwave power and CH4/CO2 molar ratio on reforming reaction were investigated. Furthermore, catalytic activity of the activated carbon was tested. And specific surface area analysis and Bothem titration method were used to explore the possible reason for the deactivation of activated carbon. The results indicate that increasing microwave power or decreasing the CH4/CO2 molar ratio can result in an increase in the reactant gas conversions as well as in the content of syngas, together with a decrease in the molar ratio of H2 and CO. It is found that an encouraging catalytic activity is achieved at the beginning, followed by a sharp loss of catalytic activity after 40 min, which is mainly caused by the change of pore structure and the reduction of functional oxygen groups. [ABSTRACT FROM AUTHOR]