Production of alcohols from cellulose by supercritical methanol depolymerization and hydrodeoxygenation

The reaction pathway and products of cellulose supercritical methanol depolymerization and hydrodeoxygenation (SCM-DHDO) were investigated. Monoalcohols, diols, alcohol ethers, and methyl esters were produced from cellulose at 300 °C with a CuMgAl mixed metal-oxide catalyst. Time-course experiments show that cellulose is rapidly solubilized and depolymerized within 1 h with C2–C4 diols being intermediates. Experiments with glucose-13C6 show that methanol is incorporated in all liquid products accounting for approximately 30–40% of the carbon in these products. Experiments with model compounds (dihydroxyacetone, isosorbide, and 5-hydroxymethylfurfural) indicate that the reaction pathway for cellulose occurs primarily through retro-aldol condensation of solubilized cellulose followed by recondensation with methanol. Methanol produces H2, CO, and CO2 through reformation with 30% of the generated H2 being incorporated into the liquid products. Analysis of the liquid products with Fourier transform ion cyclotr...