Hydrogenation of carbon monoxide on carbon monoxide reducing catalyst and solid acid. 6. Selective production of C3 and C4 hydrocarbons from synthesis gas

It was found that hybrid catalysts composed of the physical mixture of methanol synthesis catalysts and Y-type zeolites gave C/sub 3/ and C/sub 4/ paraffins from synthesis gas with a selectivity higher than 70% with little or no aromatic hydrocarbons under moderately pressurized conditions (1.0-4.1 MPa) and at fairly high temperatures (573-630K). The yield of hydrocarbon was much higher than the level estimated from the thermodynamic equilibrium of methanol formation from synthesis gas. It was clarified that the hydrogenative condition (a hydrogenation catalyst plus hydrogen) was essential for the high selectivity. Also, zeolite characteristics, which enabled short residence time of olefins in the zeolite, such as (1) large pore size, (2) small crystal size, and (3) small particle size, were essential factors.