A novel reaction system has been developed to synthesize methanol from carbon monoxide and hydrogen containing carbon dioxide as well as water by copper-based catalysts at low temperature and low pressure, compared to the present industrial process. This may be a new method for commercial methanol production. Carbon dioxide and water, which usually act as poisons to alkali metal methoxide catalyst in the low-temperature methanol synthesis reaction, play a promotional role in this new route. Accompanying alcohol, as a "catalytic liquid medium," with the aid of copper-based solid catalyst, altered the reaction path to a low-temperature direction. (C) 2001 Academic Press.