采用TPO、TPD、连续及脉冲微反技术，研究了Co/HZSM-5催化剂上甲烷二氧化碳重整反应的积炭机理，并考察了载体硅铝比及助剂Na2O、La2O3和MgO对该催化剂反应活性及抗积炭性能的影响。结果表明：积炭主要来源于CH4的解离；提高载体Si/Al比和添加助剂可有效地抑制积炭。助剂抑制积炭能力的强弱为：Na2O＞La2O3＞MgO。其中，La2O3和MgO对催化剂活性影响不大，但Na2O使催化剂活性明显降低。关联反应性能和表征结果，认为催化剂表面酸碱性是影响催化活性和抗积炭性能的重要因素。%Coke formation mechanism in CH4/CO2 reforming to syngas over Co/HZSM-5 catalysts was studied by TPO, TPD, continuous and pulse reaction techniques, and the effects of Si/Al ratio of HZSM-5 and promoters including Na2O, La2O3 and MgO on activity and coking behavior of the catalyst were investigated. The results show that CH4 decomposition is a main contributor to coke deposition, which is suppressed effectively through increasing Si/Al ratio of HZSM-5 and adding promoters. Suppression of coke deposition caused by the promoters is in the following order: Na2O＞La2O3＞MgO. Among the promoters, La2 O3 and MgO have hardly effect on the catalyst activity, while a drop is found in catalyst activity due to Na2O added. Combing the catalytic performance and the results of TPO and TPD study, it is proposed that surface acidity of the catalyst is an important factor affecting catalytic activity and resis tance to coke deposition.
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