铈钴复合氧化物催化甲烷裂解制氢及两步法制合成气实验研究  

Hydrogen Production via Direct Cracking of Methane and Two-Step Method for Syngas over Cerium Cobalt Complex Oxides Catalyst

作　　者：李孔斋[1] 王华[1] 魏永刚[1] 刘明春[1] 

机构地区：[1]昆明理工大学材料与冶金工程学院,云南昆明650093

出　　处：《中国稀土学报》2008年第2期129-134,共6页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金(50574046;50164002);国家自然科学基金重大研究计划(90610035);云南省自然科学基金资助项目(2004E0058Q);教育部高校博士学科点专项科研基金资助项目(20040674005)

摘　　要：采用共沉淀法制备了铈钴摩尔比为1∶1的复合氧化物催化剂。在固定床反应器中进行了甲烷催化裂解实验,并用空气进行了催化剂失活/活化再生循环实验,利用XRD分析手段对催化剂进行了表征。结果表明,铈钴复合氧化物催化剂对甲烷裂解和积炭选择性氧化都有良好的催化性能。600℃甲烷裂解转化率达到43%,并能在280 min的时间内保持活性。用空气能有效地活化已失活的催化剂,并且再生前30 min积炭可被高选择性(91%)地氧化为CO,通过控制再生过程中的空气流量可以将再生后期尾气中的CO和CO2有效分离,从而分别得到较高纯度的CO和CO2。XRD结果显示,多次裂解/再生循环过程,对催化剂晶体结构没有明显破坏。The cerium cobalt complex oxides catalyst with atomic ratios 1 ： 1 was prepared by co-precipitation method. The hydrogen production via the direct thermal decomposition of methane was investigated in a fixed micro-reactor system. The catalysts were characterized by means of XRD. The results showed that the cerium cobalt complex oxides catalyst had good activity for decomposition of methane to hydrogen and also for selective oxidation of carbon to CO. The conversion of methane approaches 43 % and the catalyst wasstable after 9 successive decomposition/regeneration cycles at 600 ℃. The catalyst activity could be fully regenerated by air and the remained carbon could be selectively oxidized to CO, and the selectivity of CO was more than 91% at the beginning of the catalyst regeneration. The XRD analyses indicated that there were no apparent increase in the amount of carbon remaining on the catalyst after successive regenerations and no structural changes in the catalyst.

关 键 词：甲烷裂解 铈钴复合氧化物 氢气 再生 合成气 稀土 

分 类 号：O643[理学—物理化学]