摘要
运用溶胶-凝胶法合成了同时具有介孔和三维交联通透型微米级大孔的Al2O3多孔材料,并以其为载体采用浸渍法制备得到一种新型的Pd/Al2O3整体式催化剂,考察了不同助剂Ce,Zr,La及不同的助剂负载量对甲烷催化燃烧活性的影响。实验结果表明,所合成的新型Pd/Al2O3催化剂具有良好的低温活性,在CH4体积百分数为1%,反应气体空速为6 000 h-1的实验条件下,Pd/Al2O3的起燃温度只有227℃,认为这主要是采用的Al2O3载体材料中存在的三维交联通透型微米级大孔骨架可以提供快速的传质通道,在骨架中存在的纳米级介孔能提供较大的表面积和单位容量,从而有利于提高活性组分的分散性及有效利用效率,提高催化剂的活性。助剂Zr的加入能够降低催化剂的起燃温度,而助剂Ce对催化剂活性的影响与其添加量有关。
Bimodal Al2O3 porous material with both mesopores and three-dimensional interconnected macropores in micrometer-scale was synthesized via sol-gel method.A kind of novel Pd/Al2O3 monolithic catalysts were prepared by impregnation using the as-synthesized Al2O3 porous material as the support.Influence of different additives of Ce,Zr,La and different load amount of the additives on methane combustion activity were investigated.The experimental results show that the new synthesized Pd/Al2O3 catalyst has good low temperature activity.Under the experimental conditions of 1%CH4 with reaction gas space velocity of 6 000 h-1,the ignition temperature of Pd/Al2O3 is only 227 ℃.It is considered that the three-dimensional interconnected macropores of Al2O3 support can provide fast mass transfer channel;while the nanoscale mesopores in the skeleton can provide large surface area and unit volume,and thus help to increase the catalytic activity by improving the dispersion of the active component and use efficiency.Additives of Zr can reduce the ignition temperature of the catalyst;the influence of additive of Ce on the catalyst activity depends on the loaded amount.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2012年第A02期336-340,共5页
Journal of China Coal Society
基金
国家自然科学基金资助项目(41072118)
关键词
煤矿乏风
催化活性
甲烷燃烧
PD
AL2O3
合成
VAM（Ventilation Air Methane）
catalytic activity
methane combustion
Pd/Al2O3
synthesis
