高等学校化学学报 ›› 2020, Vol. 41 ›› Issue (11): 2488-2495.doi: 10.7503/cjcu20200385

• 物理化学 • 上一篇    下一篇

Ni-SiO2催化剂空间限域维度对CH4-CO2重整反应金属抗积碳能力的影响

吴昊, 王长真(), 仇媛, 田亚妮, 赵永祥   

  1. 山西大学精细化学品教育部工程研究中心, 化学化工学院, 太原 030006
  • 收稿日期:2020-06-23 出版日期:2020-11-10 发布日期:2020-11-06
  • 通讯作者: 王长真 E-mail:czwang@sxu.edu.cn
  • 基金资助:
    国家自然科学基金(批准号(21603127);21673132, U1710221)和山西省高校科技创新项目(2020L0018)

Effect of Steric Confinement Dimension on Metal Site Anti-carbon Deposition Ability of Ni-SiO2 Catalysts in CH4-CO2 Reforming

WU Hao, WANG Changzhen(), QIU Yuan, TIAN Yani, ZHAO Yongxiang   

  1. Engineering Research Center of Ministry of Education for Fine Chemicals,School of Chemistry and Chemical Engineering,Shanxi University,Taiyuan 030006,China
  • Received:2020-06-23 Online:2020-11-10 Published:2020-11-06
  • Contact: WANG Changzhen E-mail:czwang@sxu.edu.cn
  • Supported by:
    Supported by the National Natural Science Foundation of China(21603127);the Scientific andTechnological Innovation Programs of Higher Education Institutions in Shanxi Province, China(2020L0018)

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.

关键词: 镍基催化剂, 甲烷重整, 空间限域, 限域维度, 抗积碳

Abstract:

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.

Key words: Ni-based catalyst, Methane reforming, Steric confinement, Confinement dimension, Anticarbon deposition

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