Method for the production of hydrocarbons using iron-carbon-based catalysts

A process for producing C.sub.2 + aliphatic hydrocarbons from a CO and H.sub.2 mixture comprising the step of contacting said mixture with a catalyst comprising finely divided non-pyrophoric iron-carbon catalyst particles comprising iron and carbon, in the substantial absence of silicon, a substantial portion of which is dementite, which was produced in a reaction zone in the presence of laser radiation under such conditions of laser flux density, power adsorption, concentration of iron compound reactants selected from the group consisting of iron carbonyls, iron acetylacetonate, and ferrocene, and pressure sufficient to produce non-pyrophoric iron-carbon particles having average diameters between 1 and 100 nm.