Because of the current increase of the energy consumption, (in particular in the field of transports) and of the necessity of reducing greenhouse gas emissions, it could be interesting to produce liquid synthetic motor fuels, among the various possibilities of synthetic motor fuels, the methanol appears to be the most promising. We examine the various ways to produce some ethanol from the steam natural gas reforming. This operation produces some syngas (CO+H2), which can be then transformed into ethanol following diverse processes of which we compare the advantages and the inconveniences. From the point of view of the energy efficiency we find that syngas direct conversion to ethanol has relatively highest energy ratio than other processes. We propose suitable modifications to improve the yield and selectivity for ethanol.
