Environmental regulations motivate the industries to replace conventional fuels and chemicals by those produced from biomass. In this regard, hydrodeoxygenation of lignin compounds is of a great deal of attention. Synthesis gas could be utilized instead of pure hydrogen for the cleavage of oxygen‐containing chemical bonds through hydrodeoxygenation. Following this, the utilization of synthesis gas is investigated in the present contribution. A wide range of commercial alumina‐supported catalysts is investigated. The experimental results of cyclohexanone hydrodeoxygenation in the presence of pure hydrogen and synthesis gas at 573 K and 20 bar of total pressure are presented and discussed. The whole investigated catalysts show good activity toward the hydrodeoxygenation of cyclohexanone. Methylatedbenzene derivatives are produced from cyclohexanone hydrodeoxygenation for the first time. The catalysts composed of platinum showed the best performance. By utilizing a chlorinated platinum catalyst, 89.6% cyclohexanone conversion, 100% total hydrocarbon selectivity, and 44.6% total hydrocarbon yield are obtained. In the case of syngas‐assisted hydrodeoxygenation, 80.1% cyclohexanone conversion, 100% total hydrocarbon selectivity, and 29.6% total hydrocarbon yield are obtained by utilizing the same catalyst. The presence of methylated aromatics proves the accomplishment of methanation or direct aromatization reactions in the presence of carbon oxides and hydrogen.

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Developing biomass-based strategies for liquid bio-fuels production is promising for the reduction of the aftereffects of fossil fuels. The conversion of lignin-derived intermediates such as cyclohexanone is currently of a great deal of interest. The current study aims to evaluate the molybdenum-based hydrotreating catalysts for the conversion of cyclohexanone in the presence of hydrogen. Catalytic experiments at 400 °C, 15 bar, and a range of WHSV were developed. The experiments reveal that catalyst type and reaction WHSV affect the cyclohexanone conversion, product distribution, deoxygenation efficiency, total hydrocarbon production capacity, and heating value of the product blend. The main products include C 6 cyclic and aromatic hydrocarbons and oxygenates. Cyclohexane, cyclohexene, benzene, cyclohexanol, and phenol are major products. Small quantities of methylcyclopentane and bicyclic hydrocarbons and oxygenates are also reported in some cases. Increasing WHSV reduced the cyclohexanone conversion. Cyclohexanone conversions up to 89% were observed at the lowest WHSVs over a cobalt-molybdenum sample. The highest hydrocarbon production capacity (99.53%) was managed at WHSV = 5.240 g cyclohexanone /g cat h over a cobalt-molybdenum sample, while the highest deoxygenation efficiency, i.e. 81.29% degree of deoxygenation and 5.35 C/O ratio enhancement were achieved at WHSV = 0.262 g cyclohexanone /g cat h by a nickel-molybdenum sample. The heating values would be enhanced by up to 22.7% when cyclohexanone is converted over the utilized catalysts. The larger heating value (44.90 MJ/kg, 22.7% enhancement) was obtained over a nickel-molybdenum catalyst, which is comparable to the energy density of the conventional fuels. The results reveal that the catalysts are efficient in the conversion of cyclohexanone to liquid bio-fuels.

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