摘要
考察了碱性助剂Ｋ２Ｏ，Ｌｉ２Ｏ，ＭｇＯ，Ｌａ２Ｏ３和ＣｅＯ２对Ｎｉ／γＡｌ２Ｏ３催化剂上ＣＨ４ＣＯ２重整反应活性和抗积炭能力等方面的影响．结果表明，这些助剂对催化剂的抗积炭能力都有明显的改善作用，ＣＨ４ＣＯ２重整活性在不同温度范围内也有不同程度的提高．其中，ＭｇＯ，Ｌａ２Ｏ３和ＣｅＯ２助剂的作用明显，但与添加顺序有关．先浸Ｎｉ后浸Ｍｇ制备的催化剂有较高的ＣＨ４转化率，但抗积炭能力远不如先浸Ｍｇ来得强；Ｌａ２Ｏ３的两种添加次序则差别不大，其突出作用表现在维持Ｎｉ为低价还原态、削弱ＮｉＡｌ２Ｏ３间的相互作用和促进ＣＯ２转化等方面．
The reaction activity for reforming of CH 4 with CO 2 to syngas and the resistance to carbon deposition of Ni/ γ Al 2O 3 catalyst with K 2O, Li 2O, MgO, La 2O 3 and CeO 2 as promoters were investigated using a fixed bed flow reactor as well as TG, XRD, XPS and TEM techniques, and the effect of impregnating order of promoter in preparation was also examined. All the catalyst samples with a promoter exhibit high resistance to carbon deposition, and except for K 2O and Li 2O, the other promoters are good for the reaction activity. The catalyst with MgO exhibits higher catalytic activity when MgO was added after Ni, but it is better to prevent coking if added before Ni. Among these samples, La 2O 3 promoted one has the best activity and resistance to carbon deposition, which can be attributed to maintaining the reduced Ni with lower valence, weakening the interaction of Ni with Al 2O 3 and promoting CO 2 conversion.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
1997年第5期364-367,共4页
关键词
甲烷
二氧化碳
重整
合成气
镍催化剂
Methane, Carbon dioxide, Reforming, Nickel, Alumina, Supported catalyst, Basic promoter
