Syntheses of isobutane and branched higher hydrocarbons from carbon dioxide and hydrogen over composite catalysts

The hydrogenation of carbon dioxide was examined over various composite cat alysts composed of Fe-Zn-M catalyst and zeolite. Fe-Zn-Zr/HY composite cata lyst was confirmed to be efficient for the highly selective production of i sobutane, which is regarded as a synthetic intermediate of MTBE (methyl ter t-butyl ether). The composite catalyst of Fe-Zn-Zr catalyst with H-ZMS-5 fo rmed C5+ hydrocarbons in good yield. The ratios of branched hydrocarbons in C5+ ones, which are suitable for high-octane gasoline, were over 90%.