Production of renewable hexanols from mechanocatalytically depolymerized cellulose by using ir-ReO_x/SiO₂ catalyst

Hexanols were produced in high yield by conversion of cellulose over Ir-ReO_x/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 ∼2 (v/v), 413 K, 10 MPa H₂ for 24 h. 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 watersoluble oligosaccharides but also promoted the hydrogenolysis activity of Ir-ReO_x/SiO₂ catalyst. The role of n-decane was to extract hexanols and to suppress over-hydrogenolysis of hexanols to n-hexane.