For the soot-free production of a fuel gas mixture containing carbon monoxide, hydrogen and gaseous hydrocarbons by partial oxidation of liquid hydrocarbons with air, with air numbers below 0.3 and temperatures between 600.degree. and 800.degree. C., a metal catalyst is employed according to the invention, which is prepared by forming shaped bodies composed of an aluminum alloy which contains 15 to 35 wt. % silicon, and subjecting the shaped bodies for at least 10 hours at temperatures between about 600.degree. and about 800.degree. C. to an oxidizing atmosphere and for at least 10 hours at temperatures between about 600.degree. and about 800.degree. C. to gaseous or gasified hydrocarbons for the partial conversion of the aluminum in the shaped body to .alpha.-Al.sub.2 O.sub.3 and for the partial conversion of the silicon in the shaped body to .beta.-SiC, respectively.