Hydrogenation of carbon dioxide to formic acid

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 81 KB
• Volume: 88
• Category: Article
• ISSN: 0926-860X
• DOI: 10.1016/0926-860x(92)80221-w

✦ Synopsis

N16

of Chemical Technology, Shanghai, have studied the methane coupling reaction over NaCI/Sm2Os, NaCUMgO, NaCl-SmCl&tgO and other catalysts in the temperature range from 686°C to 790°C at a pressure of 0.1 MPa (Chin. J. Petrochem. Tech., 26 (1991) 299). The ratio of CH&s:Ns in the feed was 1:2:5, the flow rate being 56 ml min-' (W/F=2.4 g s ml-'). Among the catalysts tested, 29 mol-% NaCI/MgO was found to have the highest c;! hydrocarbon yield, 25.8%, with an ethene selectivity over 89% at 799°C.

The reaction mechanism was discussed. The authors suggest that in the catalyst series NaCI/MgO, the MgO acts both as catalyst and support. The basic sites on the surface are important for the activation of methane. The acid-base property of MgO is modified by the NaCI, thus increasing the c2 selectivity. The role of the CT anion is possibly to act as a bridge in the intermediate steps to make the formation of the C-C bond easier.