Acta Chimica Sinica ›› 2004, Vol. 62 ›› Issue (21): 2143-2149. Previous Articles     Next Articles

富氢气氛下CO选择性氧化催化剂Pt/γ-Al2O3中添加钴的作用

严菁1, 马建新2, 周伟2   

  1. 1. 华东理工大学工业催化研究所, 上海, 200237;
    2. 同济大学新能源汽车工程中心, 上海, 200092
  • 投稿日期:2004-02-09 修回日期:2004-04-28 发布日期:2014-02-17
  • 通讯作者: jxma@fcv-sh.com
  • 作者简介:马建新,Email:jxma@fcv-sh.com;Fax:(021)69589461

Effect of Cobalt in Modifying Pt/γ-Al2O3 Catalyst for Preferential Oxidation of CO in Hydrogen-rich Stream

YAN Jing1, MA Jian-Xin2, ZHOU Wei2   

  1. 1. Institute of Industrial Catalysis, East China University of Science and Technology, Shanghai 200237;
    2. Clean Energy Automotive Engineering Center, Tongji University, Shanghai 200092
  • Received:2004-02-09 Revised:2004-04-28 Published:2014-02-17

Carbon monoxide is a poison to the Pt anode in proton exchange membrane fuel cell (PEMFC). Preferential oxidation (PROX) over Pt/γ-Al2O3 catalyst is an effective method to reduce CO in hydrogen rich gas streams to a tolerant level. In this paper, the effect of adding Co to Pt/γ-Al2O3 catalyst on lowering Pt-loading and improving catalytic properties was investigated. Experimental results showed that the addition of Co to Pt/γ-Al2O3 could not only improve the activity at low-temperature but also reduce significantly the Pt-loading in the catalysts. Over the catalysts with Pt-loading of wPt=0.01 and Co loading of wCo=0.015~0.03 and in the conditions of temperature at 120℃ and φO2CO=1.0, the conversion of CO could reach over 99% and the selectivity of O2 was 47%. The results of characterization by XRD, CO-TPD, H2-TPR and FTIR revealed that in the promoted catalyst there existed incompletely reduced cobalt oxides, which not only provided active oxygen to CO to the formation of CO2 but also affected the electronic property of Pt, leading to a more difficult reduction of Pt. Furthermore, the addition of Co weakened the adsorption of CO on Pt, inhibited the linear adsorption of CO on Pt, and increased the surface adsorption of bicarbonate and formate species. Bicarbonate species diminished quickly and turned into CO2 over Co/Pt/γ-Al2O3 with increasing temperature.

Key words: preferential oxidation, carbon monoxide, hydrogen-rich stream, cobalt, Pt/γ-Al2O3,fuel cell