Direct catalytic conversion of methane and light hydrocarbon gases. Quarterly report No. 9, October 1--December 31, 1988

The goal of this research is to develop catalysts that directly convert methane and light hydrocarbons to intermediates that later can be converted to either liquid fuels or value-added chemicals, as economics dictate. During this reporting period, we completed our IR spectroscopic examination of the Ru{sub 4}/MgO and FeRu{sub 3}/MgO systems under nitrogen and methane by examining FeRu{sub 3}/MgO under methane. This system behaved quite differently than the same system under nitrogen. Under methane, only one very broad peak is observed at room temperature. Upon heating, the catalyst transformed so that by 300{degrees}C, the spectrum of FeRu{sub 3}/MgO under methane was the same as that of Ru{sub 4}/MgO. This suggests that methane promotes the segregation of the metals in the mixed metal system. The differences in catalytic activity between the FeRu{sub 3}/MgO and Ru{sub 4}/MgO systems may then be due to the presence of IR transparent species such as iron ions which cause different nucleation in the ruthenium clusters. We examined several systems for activity in the methane dehydrogenation reaction. Focusing on systems which produce C{sub 6} hydrocarbons since this is the most useful product. These systems all displayed low activity so that the amount of hydrocarbon product is very low. Some C{sub 6} hydrocarbon is observed over zeolite supports, but its production ceases after the first few hours of reaction. We prepared a new system, Ru{sub 4} supported on carbon, and examined its reactivity. Its activity was very low and in fact the carbon support had the same level of activity. We synthesized four new systems for examination as catalysts in the partial oxidation of methane. Three of these (PtTSPC/MgO, PtTSPC and PdTSPC on carbon) are analogs of PdTSPC/MgO. This system is of interest because we have observed the production of ethane from methane oxidation over PdTSPC/MgO at relatively low temperatures and we wished to explore its generality among close analogs