Study of Catalysts for Hydrogen Production by the High Temperature Steam Reforming of Methanol

✍ Scribed by C. Zhang; Z. Yuan; N. Liu; S. Wang; S. Wang

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 249 KB
• Volume: 6
• Category: Article
• ISSN: 1615-6846
• DOI: 10.1002/fuce.200600010

✦ Synopsis

Abstract

In the present study, a series of Ir‐based catalysts, supported on Al~2~O~3~, ZrO~2~, CeO~2~, and Ce~x~Zr~1‐x~O~2~, are investigated for the production of hydrogen by the high temperature steam reforming of methanol (SRM). Results show that CeO~2~ and Ce~x~Zr~1‐x~O~2~ can promote the CO water gas shift (WGS) reaction, which is involved in the SRM network. Ir/CeO~2~ exhibits a better initial methanol conversion and its stability can be enhanced by the addition of ZrO~2~ to CeO~2~. The TPR and XRD characterization of the CeO~2~‐ZrO~2~ mixed oxides shows that Ce~0.5~Zr~0.5~O~2~ is the optimum support in maintaining catalyst activity, as well as stability. The addition of the precious metal Pt to Ir/Ce~0.5~Zr~0.5~O~2~ demonstrates a synergistic effect and can obviously increase the selectivity of H~2~. In the meantime, the CO content in the reformate products decreases from 9 mol‐% to 6 mol‐%. Under the conditions of H~2~O__/__CH~3~OH=1.5 (molar ratio), LHSV=2.5 h^–1^, and a reaction temperature of 400 °C, a 92% methanol conversion is obtained during a 200 hour test on a 0.3%Ir‐0.3%Pt/Ce~0.5~Zr~0.5~O~2~ catalyst and the stability is better than that of a commercial copper‐based catalyst.