摘要
CoMoK/Al_2O_3耐硫水煤气变换催化剂中加入La_2O_3后其活性与含量和处理温度有关。含有0.5—1.0％La_2O_3的催化剂和载体经600℃处理活性和耐热性最高。在500℃进行强化反应后La助化的催化剂活性下降～50％,而无La的下降～70％。以H_2S/H_2重新处理减活后的催化剂可以使活性逐渐恢复,但含La的比不含La的恢复得快。由催化剂的硫化过程和程序升温还原及吡啶吸附实验未能发现两种催化剂有明显的区别。XPS测定结果发现La助化的催化剂在反应时,其Mo可以保持较好的分散和较少形成Mo^(6+),而Mo^(6+)对反应是无活性的。
A more active and heat resistant water gas shift catalyst Co Mo K/Al_2O_3 has beenobtained by modification of Al_2O_3 support with La_2O_3 (ranging from 0.5 to 1 wt. % basedon the catalyst) and aftertreatment at 600℃. La-promoted catalyst lost～50% of itsinitial activity after water gas shift reaction which is accelerated at 500℃, while theunpromoted catalyst lost～70%. The activity of deteriorated catalyst can be restored bytreatment with H_2S/H_2, but the rate of reactivation of the La-promoted is greater thanthat of the unpromoted. No obvious difference was found in the sulfidation of catalystwith H_2S/H_2 and temperature programmed reduction determination and pyridine adsorptionon sulfided catalyst. XPS data indicated that a better dispersion of Mo and less Mo^(6+)formed during water gas shift reaction on the La-promoted catalyst.
出处
《应用化学》
CAS
CSCD
北大核心
1989年第2期1-4,共4页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金
关键词
钴钼催化剂
水煤气变换
镧助化剂
Cobalt molybdenum catalyst
Water gas shift
Lathanum promoter
Sulfur resistant
