Cu/ZnO/Al2O3 Water-gas shift catalysts for practical fuel cell applications: the performance in shut-down/start-up operation
Cu/ZnO/Al2O3 Water-gas shift catalysts for practical fuel cell applications: the performance in shut-down/start-up operation
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用于实际燃料电池应用的 Cu/ZnO/Al2O3 水煤气变换催化剂：关闭/启动操作的性能
DOI：
10.1016/j.ijhydene.2008.12.081
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发表时间：
2009-03-01
影响因子：
7.2
通讯作者：
Fan, Kangnian
中科院分区：
文献类型：
--
作者：
Guo, Pinjun;Chen, Liangfeng;Fan, Kangnian
采用共沉淀法制备了铜/氧化锌/氧化铝催化剂，并对其水煤气变换(WGS)反应性能进行了评价。研究了焙烧温度对BET比表面积和微晶尺寸的影响。在WGS反应中，铜/氧化锌/氧化铝催化剂在关闭/启动过程中不断失活，这是移动和家用燃料电池系统的日常需求。其中，焙烧温度为450℃时制备的催化剂活性和稳定性最好，经3次启停循环后，CO转化率仅下降12.8%。催化剂失活的原因是在循环操作下，由于氧化物的退化，导致活性中心被锌铝酸铝(16)CO3.4H(2)O封闭或劣化。通过在空气中焙烧然后再还原的方法去除羟基碳酸酯物种可以恢复稳定的WGS活性，但在随后的关机/启动操作中，再生的催化剂经历了更严重的失活。(C)2009年国际氢能协会。爱思唯尔有限公司出版。保留所有权利。
The Cu/ZnO/Al2O3 catalysts were prepared by the coprecipitation method, and were evaluated in the water-gas shift (WGS) reaction. The effects of the calcination temperature on the BET surface area and crystallite size were characterized. In WGS reaction, the Cu/ZnO/Al2O3 catalysts suffered from continuous deactivation in shut-down/start-up operation - the daily requirement for mobile and residential fuel cell systems. Among them, the Cu/ZnO/Al2O3 catalyst prepared at the calcination temperature of 450 degrees C showed the best activity and stability, with the decrement of the CO conversion of only 12.8% after three shut-down/start-up cycles. Deactivation of the Cu/ZnO/Al2O3 catalysts is attributed to the blocking or deterioration of the active sites by Zn6Al2(OH)(16)CO3.4H(2)O resulting from the degeneration of the oxides under cyclic operations. Removal of the hydroxycarbonate species by calcination in air followed by re-reduction could restore the steady-state WGS activity; however, the regenerated catalyst underwent much severe deactivation in subsequent shut-down/start-up operation. (c) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.