For production of organic compounds such as MeOH there is passed over a suitable catalyst such as Fe oxide, in a circulating system, a gas mixture containing a large proportion of inert gas, such as a "power-gas", which has been scrubbed to remove CO2 and then contains CO about 15.3%. H2 about 30.6%, CH4 about 2.8%, and N2 about 51.3%, and part of the residual gas mixture is removed and continuously replaced by fresh gas to constantly maintain a proportion of about 12% CO and 24% H2 in the circulating gas. Temperatures of 200°-500° and pressures above 50 atm. are suitable for the process. It is stated that as good yields may be obtained as when employing gases richer in reacting constituents.