Na2WO4-Mn/mullite Catalysts for Oxidative Coupling of Methane

Authors :: Viravathana, Pinsuda
Sukwises, Narathorn
Boonpa, Siriporn
Larpkiattaworn, Siriporn
Source :: Advanced Materials Research; July 2011, Vol. 287 Issue: 1 p3015-3019, 5p
Publication Year :: 2011
Abstract: The catalysts, 5 wt% Na<subscript>2</subscript>WO<subscript>4</subscript> -2 wt% Mn on mullites sintered at 1200<superscript> o</superscript>C, 1300<superscript> o</superscript>C, 1400<superscript> o</superscript>C, and 1500 <superscript>o</superscript>C, were prepared by incipient wetness impregnation method for the oxidative coupling of methane (OCM) reaction in a fixed-bed quartz tube reactor. These catalysts were characterized by XRD, XPS and BET method. The XRD pattern of Na<subscript>2</subscript>WO<subscript>4</subscript>-Mn/mullite indicated that the main crystal phase of metal oxide was MnWO<subscript>4</subscript>. From the XPS spectra, the results revealed the information on Na, W and Mn species distributed on the catalyst surface. For catalytic activity testing, Na<subscript>2</subscript>WO<subscript>4</subscript>-Mn/mullite sintered at 1300 <superscript>o</superscript>C showed the highest C<subscript>2</subscript> selectivity of 11.4% and Na<subscript>2</subscript>WO<subscript>4</subscript>-Mn/mullite sintered at 1400 <superscript>o</superscript>C showed the highest CH<subscript>4 </subscript>conversion of 56.6%.