摘要
用 XPS和 TPR谱学表征方法 ,研究钾助剂对负载型 Co-Mo-K-O/γ-Al2 O3水煤气耐硫变换催化剂的作用 .XPS表征显示 ,硫化态催化剂随着钾添加量的增加 ,低价态钼和 S2 - 增加 ,( S-S) 2 - 受抑制 ,( Mo4+ +Mo5 + ) /Mo6 + 质量比为 0 .8～ 1和较多的 S2 - 物种有利于提高催化剂的低温活性 .TPR表征结果示出 ,硫化态及工作态催化剂皆出现α、β 2个吸氢峰 ,可分别归属 Mo6 + → Mo5 + 和 Mo5 + → Mon+ ( n=4 ,3,2 )的还原过程 ;工作态催化剂 α峰峰温较硫化态低 ,β峰为宽峰带低价钼混合峰 ;吸氢峰的大小与催化剂低温活性密切相关 .
The XPS, TPR techniques were used to study the promotion effect of K 2CO 3 to the supported catalyst Co Mo K O/ γ Al 2O 3 for water gas shift. The XPS results show that the amount of low valence molybdenum and S 2- increases with increase of the content of K in sulfured catalyst, and (S S) 2- is suppressed. It is found that keeping the ratio (Mo 4+ +Mo 5+ )/Mo 6+ at 0 8～1 level and remaining more S 2- species on the catalyst are in favor of the improvement of the catalytic activity at low temperature. Two hydrogen adsorped peaks of TPR, namely α and β peaks, which can be ascribed to Mo 6+ →Mo 5+ and Mo 5+ →Mo n + ( n =4,3,2) reduction processes respectively, appear both at sulfured state and functioning state. The experiment results indicate that there is a close relation between the altitude of the peaks and the activity of the catalyst at low temperature.
出处
《应用化学》
CAS
CSCD
北大核心
2001年第1期25-28,共4页
Chinese Journal of Applied Chemistry
基金
厦门大学基金!项目 (1999~ 2 0 0 1
K0 10 0 5 )
