摘要
制备了3种化学组成相同但金属活性位点空间结构不同的Ni-SiO2催化剂(Ni/SiO2负载型催化剂、Ni/SBA-15介孔结构催化剂和Ni@SiO2核壳结构催化剂),考察了不同空间限域维度及结构对CH4-CO2重整反应活性金属抗积碳机制的影响规律.结果表明,Ni/SiO2催化剂无空间限域效应,抗积碳能力最弱,表现出最差的稳定性;Ni/SBA-15催化剂存在部分空间限域效应,抗积碳能力明显提高,表现出较好的稳定性但是仍有失活;Ni@SiO2催化剂具有完全几何限域效应,抗积碳能力最强,表现出最优的稳定性.
The sintering and carbon deposition of active sites are the main obstacles for the industrial application of methane reforming over Ni-based catalysts.As for the various improvement approaches,the use of steric geometry limiting structure can effectively limit the sintering and carbon deposition of Ni particles.However,there is still a lack of systematic understanding of their relationships based on the confinement dimension.In this paper,three Ni-SiO2 catalysts(i.e.,traditional supported Ni/SiO2,mesoporous Ni/SBA-15 and core-shell Ni@SiO2)with the same chemical composition but different metal exposure structures were prepared to investigate the influence of different steric limiting dimensions/structures on the metals’anti-carbon deposition mechanism in CH4-CO2 reforming.The results showed that Ni/SiO2 has little steric limiting effect,thus showing the weakest carbon resistance ability and the worst stability.The Ni/SBA-15 has partial steric limiting effect and its anti-carbon deposition ability is significantly improved,while Ni@SiO2,which has a complete geometric limiting effect,shows the strongest carbon resistance ability with the optimal stability.
作者
吴昊
王长真
仇媛
田亚妮
赵永祥
WU Hao;WANG Changzhen;QIU Yuan;TIAN Yani;ZHAO Yongxiang(Engineering Research Center of Ministry of Education for Fine Chemicals,School of Chemistry and Chemical Engineering,Shanxi University,Taiyuan 030006,China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第11期2488-2495,共8页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21603127,21673132,U1710221)
山西省高校科技创新项目(批准号:2020L0018)资助.
关键词
镍基催化剂
甲烷重整
空间限域
限域维度
抗积碳
Ni-based catalyst
Methane reforming
Steric confinement
Confinement dimension
Anticarbon deposition
