摘要
通过焙烧由共沉淀法制备的类水滑石化合物(HTLcs)前驱体,制备了一系列不同n(Mg)/n(Al)比(0.5,1,2和3)的Mg(Ni,Al)O复合氧化物催化剂。将该催化剂用于甲烷二氧化碳重整反应(CRM)中,并考查了Mg/Al比对催化剂活性的影响。借助XRD,BET,H2-TPR,CO2-TPD以及O2-TPO等表征手段研究催化剂结构和催化性能之间的关系。结果表明催化剂的催化活性和抗积炭性能与Mg/Al比有关。高Mg/Al比的催化剂表现出较好的催化活性和抗积炭性能,而当n(Mg)/n(Al)=1时催化剂的催化的活性和稳定性最佳,且催化剂表面生成的积炭量最少。MgAl2O4和MgO共存使催化剂具有强的金属与载体作用力,适当的CO2吸附能力,这导致催化剂具有较好的催化活性和较强的抗积炭能力。
Mg(Ni,Al)O composite oxide catalysts with different Mg/Al molar ratios(0.5,1,2 and 3)were obviously affected by crystal size.The nano-sized ZSM-5 zeolite exhibited excellent catalytic activity due to its large external surface area,short diffuse path length and good acid site accessibility.The optimal reaction conditions for the nano ZSM-5 zeolite were determined by experiments as follows:0-0.1MPa,360-380℃,and feed rate of 300-400mL/h.prepared by calcining the hydrotalcite-like compounds(HTLcs)precursors obtained by co-precipitation.The obtained catalysts were used in the CO2 reforming of CH4(CRM)and the effect of Mg/Al ratios on the catalytic performance was investigated.XRD,N2 adsorption-desorption,H2-TPR,CO2-TPD and O2-TPO-MS techniques were employed to elucidate the relationship between structure and catalytic performance.The results showed that the catalytic activity and and anti coking performance of the catalysts strongly relied on the Mg/Al ratio.The catalysts with higher Mg/Al ratios exhibited better catalytic activity and coke resistance,and the catalyst with the Mg/Al molar ratio of 1 had the best catalytic activity and stability,and the amount of carbon deposition on the catalyst surface was the least.The coexistence of MgAl2O4 and MgO endows the catalyst with strong metal-support interaction and proper CO2 adsorption capacity,which results in better catalytic activity and strong carbon deposition resistance.
作者
黄艳丽
李晓东
黄伟
HUANG Yan-li;LI Xiao-dong;HUANG Wei(Key Laboratory of Coal Science and Technology,Ministry of Education of China and Shanxi Province,Taiyuan University of Technology,Taiyuan 030024,China;School of Chemistry and Chemical Engineering,Jinzhong University,Jinzhong 030619,China)
出处
《天然气化工—C1化学与化工》
CAS
CSCD
北大核心
2019年第6期8-13,19,共7页
Natural Gas Chemical Industry
基金
国家高技术研究发展计划(2013AA051201)
国家科技支撑计划(2013BAC14B04)
国家自然科学基金重点资助项目(21336006)
