METHANATION OF CARBON-DIOXIDE OVER LANI(4)X-TYPE INTERMETALLIC COMPOUNDS AS CATALYST PRECURSOR

The hydrogenation of carbon dioxide is catalyzed over intermetallic compounds LaNi(4)X (X=Ni Cr, Al, Cu) at a reaction temperature as low as 250 degrees C under 5 MPa, where LaNi5 and LaNi4Cr are significantly active. On the basis of X-ray diffraction analyses of the catalysts after the reaction, the catalytic activity seemingly depends on the amounts of metallic nickel formed by decomposition of the intermetallic compounds during the reaction, and the compounds preserving the alloy structure are less active.