Production of Renewable Hexanols from Mechanocatalytically Depolymerized Cellulose by Using Ir-ReOx/SiO2 catalyst

Hexanols were produced in high yield by conversion of cellulose over Ir-ReOx/SiO2 (molar ratio Re/Ir=2) catalyst in biphasic reaction system (n-decane+H2O). The cellulose was depolymerized by mechanocatalysis with the aid of H2SO4. The influence of solvent amount, reaction temperature and hydrogen pressure was systematically investigated and the highest yield of hexanols reached 60% under the conditions of n-decane/water approximate to 2 (v/v), 413K, 10MPa H-2 for 24h. Mechanocatalytic depolymerization of cellulose with the aid of H2SO4 or HCl and the use of sufficient n-decane were very crucial for the production of hexanols. H2SO4 not only catalyzed cellulose to water-soluble oligosaccharides but also promoted the hydrogenolysis activity of Ir-ReOx/SiO2 catalyst. The role of n-decane was to extract hexanols and to suppress over-hydrogenolysis of hexanols to n-hexane.