Reduction of formic acid to methanol under hydrothermal conditions in the presence of Cu and Zn.

Formic acid is the main breakdown product of mild hydrothermal treatment of carbohydrates. Further conversion to methanol was achieved using Cu as catalyst and Zn as reductant under hydrothermal conditions of 250-325 °C for 3-12 h. Both Cu and Zn used were commercial Cu and Zn powders with particle sizes of 200 mesh. A methanol yield of 32% was achieved at 300 °C for 5h with 6.5 mmol of Cu, 12 mmol of Zn and a filling rate of 44%. Thus, this process may provide a promising solution to producing methanol from biomass by converting carbohydrates into formic acid.