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将柠檬酸(CA)作为络合剂添加至CeO_2-Al_2O_3复合载体中,并考察了CA对MoO_3/CeO_2-Al_2O_3催化剂耐硫甲烷化性能的影响。活性评价结果显示,催化剂活性随柠檬酸添加量的增大而增大,当n(CA)/n(Ce)为3时,CO转化率可达60%。催化剂BET、XRD、H2-TPR及XPS等表征结果表明,在CeO_2-Al_2O_3复合载体中加入CA,可以增大载体及催化剂的比表面积,使Mo物种分散性提高。同时,CA对Ce物种起络合作用,致使催化剂表面Ce元素含量明显增加,进而减弱了活性组分Mo物种与载体间相互作用力,并最终导致了催化剂活性的提升。
The citric acid (CA) was added as a complexing agent to CeO_2-Al_2O_3 composite support, and the effect of CA on the desulfurization methanation performance of MoO_3 / CeO_2-Al_2O_3 catalyst was investigated. The results of activity evaluation showed that the catalyst activity increased with the addition of citric acid, and the CO conversion reached 60% when n (CA) / n (Ce) was 3. The results of BET, XRD, H2-TPR and XPS showed that the addition of CA to the CeO_2-Al_2O_3 composite support increased the specific surface area of the support and the catalyst and improved the dispersibility of the Mo species. At the same time, CA complexed Ce species, resulting in a significant increase of Ce content on the surface of the catalyst, which further weakened the interaction between the active species Mo species and the support and finally led to the increase of the catalyst activity.