We report the complete ethanolysis of Kraft lignin over an α-MoC1-x /AC catalyst in pure ethanol at 280 °C to give high-value chemicals of low molecular weight with a maximum overall yield of the 25 most abundant liquid products (LP25) of 1.64 g per gram of lignin. The LP25 products consisted of C6 -C10 esters, alcohols, arenes, phenols, and benzyl alcohols with an overall heating value of 36.5 MJ kg(-1) . C6 alcohols and C8 esters predominated and accounted for 82 wt % of the LP25 products. No oligomers or char were formed in the process. With our catalyst, ethanol is the only effective solvent for the reaction. Supercritical ethanol on its own degrades Kraft lignin into a mixture of small molecules and molecular fragments of intermediate size with molecular weights in the range 700-1400, differing in steps of 58 units, which is the weight of the branched-chain linkage C3 H6 O in lignin. Hydrogen was found to have a negative effect on the formation of the low-molecular-weight products.

One-pot complete catalytic ethanolysis of Kraft lignin into C6–C10 chemicals, that is, aliphatic alcohols, esters, phenols, benzyl alcohols, and arenes, is achieved with a batch reactor over a number of supported molybdenum-based catalysts at 553 K in pure ethanol under autogenous pressure of 10.6 MPa. Metallic molybdenum, its carbide, and nitride all show remarkable activity, with the carbide and metallic catalysts giving the higher overall yields: 1640 and 1390 mg/g lignin, respectively. The major phases composing the catalysts are well-preserved after the reaction; however, the detection of Mo­(V) species verifies the partial oxidation of molybdenum, which leads to the formation of the dissociative Mo species, such as molybdenum V ethoxide, in the fluid phase. Through the product analysis and catalyst characterization, the common route of lignin conversion to value added chemicals over the Mo-based catalyst is presented in detail. Kraft lignin is first fragmented into segments with m/z ∼ 700–1400 via a noncatalytic ethanolysis process. Meanwhile, the main active Mo­(V) species dissociate from the solid catalyst into the fluid due to the interaction of ethanol. Then mainly the dissociative species catalyze, with the participation of the radicals, the further degradation of the segments into small molecules.

We report the complete ethanolysis of Kraft lignin over an a-MoC 1Àx /AC catalyst in pure ethanol at 280 8C to give high-value chemicals of low molecular weight with a maximum overall yield of the 25 most abundant liquid products (LP25) of 1.64 g per gram of lignin. The LP25 products consisted of C 6 -C 10 esters, alcohols, arenes, phenols, and benzyl alcohols with an overall heating value of 36.5 MJ kg À1 . C 6 alcohols and C 8 esters predominated and accounted for 82 wt % of the LP25 products. No oligomers or char were formed in the process. With our catalyst, ethanol is the only effective solvent for the reaction. Supercritical ethanol on its own degrades Kraft lignin into a mixture of small molecules and molecular fragments of intermediate size with molecular weights in the range 700-1400, differing in steps of 58 units, which is the weight of the branched-chain linkage C 3 H 6 O in lignin. Hydrogen was found to have a negative effect on the formation of the low-molecularweight products.

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An activated carbon supported α-molybdenum carbide catalyst (α-MoC1-x/AC) showed remarkable activity in the selective deoxygenation of guaiacol to substituted mono-phenols in low carbon number alcohol solvents. Combined selectivities of up to 85% for phenol and alkylphenols were obtained at 340 °C for α-MoC1-x/AC at 87% conversion in supercritical ethanol. The reaction occurs via consecutive demethylation followed by a dehydroxylation route instead of a direct demethoxygenation pathway.

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