Catalytic Valorization of Sugarcane Bagasse to Chemicals and Aviation Fuel Precursors

Abstract

Utilization of renewable resources to produce value-added chemicals is highly desirable in biorefineries. However, the direct use of lignocellulosic biomass is difficult, with current processes requiring expensive multistep fractionation and downstream isolation steps such as steam explosion or organosolv treatments followed by enzymatic or chemical hydrolysis. Here, we describe the use of a homogeneous Al catalyst for the direct one-pot hydrolysis and dehydration of sugarcane bagasse to levulinic acid and concomitant formation of an immobilized AlOOH/C hydrochar residue, which finds value as a solid acid catalyst. A range of Al-containing metal salts were screened for the acid-catalyzed hydrothermal depolymerization of sugarcane bagasse, with AlCl 3 found to be most active and selective for levulinic acid production, with a yield of 39 wt % relative to the dry biomass in 6 h at 210 °C. In the presence of a Rh(CO) 2 (acac) and tri(2-furyl)phosphine cocatalyst, the resulting acidic AlOOH/C hydrochar is efficient for the one-pot twostep cascade of hydroformylation of 1-alkenes with CO/H 2 to form linear and branched aldehydes, and their subsequent hydroxyalkylation with 2-methylfuran to form oxygenated jet fuel precursors. The functionalized AlOOH/C hydrochar support is recyclable for the hydroxyalkylation step with minimal loss of activity.