摘要
采用溶胶 凝胶法和超临界干燥 (SCD)技术制备了超细二元NiO Al2 O3和三元NiO La2 O3 Al2 O3催化剂 ,并以浸渍超细氧化铝载体和普通氧化铝载体制得的二元和三元催化剂为对比 ,考察了不同制备方法对催化剂上CH4 CO2 重整反应性能的影响 .结果表明 ,超细催化剂表现出很高的高温催化活性、选择性和显著的抗积碳能力 ,即使不含助剂的超细二元催化剂也明显优于含镧助剂的负载三元催化剂 ,而含镧的超细三元催化剂又好于超细二元催化剂 ,显示了溶胶 凝胶法和SCD制备技术的优越性 .重整反应气氛下催化剂的活性表面是可变和可恢复的 ,而高活性、高选择性及高抗积碳能力与合理的产品分布是一致的 .
Superfine binary NiO Al 2O 3 and ternary NiO La 2O 3 Al 2O 3 catalysts were prepared by sol gel and supercritical drying (SCD) techniques. Compared with traditional binary and ternary catalysts prepared by impregnating superfine alumina support or commercial alumina, the activity and resistance to carbon deposition over these catalysts for CH 4 reforming with CO 2 were investigated. The results showed that the superfine catalysts exhibit very high activity, selectivity and thermostability, particularly in the reaction at above 1?073 K. Their resistance to carbon deposition is so high that it decreases in following sequence: UNLA>UNAINUA>INLA. The excellent performance of UNLA implies that the new preparation method of sol gel and SCD techniques is more suitable for preparing nickel based catalysts for CH 4 reforming with CO 2 than conventional methods. It is also found that the active surface may be changed and can be recovered under the reaction conditions, and that the high activity may be obtained often accompanied by high selectivity, high resistance to carbon deposition and good product distribution.
出处
《催化学报》
CSCD
北大核心
2000年第4期309-313,共5页
基金
国家博士点基金!资助项目 ( 970 0 561 8)
关键词
镍基催化剂
甲烷
二氧化碳
重整反应
积碳
制备
preparation method
superfine aerogel
nickel based catalyst
methane
carbon dioxide
reforming
carbon deposition
