物理化学学报 >> 2011, Vol. 27 >> Issue (03): 697-704.doi: 10.3866/PKU.WHXB20110309

催化和表面科学 上一篇    下一篇

Ni-Co双金属催化剂上沼气重整制氢机理

徐军科1,2, 沈利红2, 周伟1,3, 马建新1,3   

  1. 1. 同济大学新能源汽车工程中心, 上海 201804;
    2. 上海市宝山区环境监测站, 上海 201901;
    3. 同济大学汽车学院, 上海 201804
  • 收稿日期:2010-09-27 修回日期:2010-11-22 发布日期:2011-03-03
  • 通讯作者: 马建新 E-mail:jxma@tongji.edu.cn
  • 基金资助:

    科技部国际合作重点项目(2007DFC61690)及汉高同济教席(081591)资助

Mechanism of Biogas Reforming for Hydrogen Production over Ni-Co Bimetallic Catalyst

XU Jun-Ke1,2, SHEN Li-Hong2, ZHOU Wei1,3, MA Jian-Xin1,3   

  1. 1. Clean Energy Automotive Engineering Center, Tongji University, Shanghai 201804, P. R. China;
    2. Shanghai Baoshan Environmental Monitoring Station, Shanghai 201901, P. R. China;
    3. School of Automotive Engineering, Tongji University, Shanghai 201804, P. R. China
  • Received:2010-09-27 Revised:2010-11-22 Published:2011-03-03
  • Contact: MA Jian-Xin E-mail:jxma@tongji.edu.cn
  • Supported by:

    The project was supported by the Key Project of International Cooperation of the Ministry of Science and Technology of China (2007DFC61690) and Henkel Professorship of Tongji University, China (081591).

摘要:

用传统湿式浸渍法制备了La2O3掺杂的商业γ-Al2O3负载的沼气重整催化剂Ni-Co/La2O3-γ-Al2O3, 并用程序升温加氢(TPH)、程序升温氧化(TPO)、程序升温表面反应(TPSR)、程序升温脱附(TPD)及脉冲实验对催化剂进行了表征. 结果表明, 沼气重整过程中Ni-Co/La2O3-γ-Al2O3催化剂上的表面碳物种主要来源于CH4的裂解, CO2的贡献很小. CH4裂解能够产生三种活性不同的碳物种, 即Cα、Cβ与Cγ. 随着反应的进行, Cα物种减小而Cβ与Cγ物种增加, 且Cγ物种能够转变为惰性的石墨碳. 重整反应过程中CH4与CO2的活化能相互促进. 催化剂表面的O物种与C反应生成CO或与CHx反应生成CHxO再分解为CO与吸附态的H物种, 可能是Ni-Co/La2O3-γ-Al2O3催化剂上沼气重整的速率控制步骤.

关键词: 镍, 钴, 双金属催化剂, 沼气重整, 制氢, 机理

Abstract:

Ni-Co bimetallic catalysts supported on commercial γ-Al2O3 modified with La2O3 were prepared by conventional incipient wetness impregnation for biogas reforming. The catalysts were characterized using temperature-programmed hydrogenation (TPH), temperature-programmed oxygenation (TPO), temperature-programmed surface reaction (TPSR), temperature-programmed desorption (TPD), and a pulse experiment. During biogas reforming the surface carbon species on Ni-Co/La2O3-γ-Al2O3 originated mainly from the cracking of CH4 and the contribution of CO2 was insignificant. Cracking of CH4 results in three carbon species of Cα, Cβ, and Cγ, which have different reaction activities. During the reaction, the amount of Cα decreased but Cβ and Cγ increased. In addition, Cγ could be changed into inactive graphite carbon. The activation of CH4 and CO2 was mutually promoted in the reforming reaction. It was revealed that the controlling step for biogas reforming over the Ni-Co/La2O3-γ-Al2O3 catalyst could be the reaction of the surface species of O with C to form CO or with CHx to give CHxO followed by the formation of CO and adsorbed H.

Key words: Nickel, Cobalt, Bimetallic catalyst, Biogas reforming, Hydrogen production, Mechanism

MSC2000: 

  • O643