Partial oxidation was applied to enhance the gasification efficiency of the supercritical water gasification of biomass. Hydrogen peroxide was employed as oxygen source and effect of partial oxidation on supercritical water gasification of 0.6M glucose, a model compound of biomass, and cabbage slurry was experimentally investigated using a bench-scale continuous reactor. For gasification at 873K, gasification efficiency close to unity was obtained, but at a lower temperature, the value decreased. The effect of partial oxidation was thus investigated at lower temperatures. Partial oxidation was effective in improving gasification efficiency for both glucose solution and cabbage slurry. The improvement of gasification efficiency was accompanied with higher yield of both hydrogen and carbon monoxide. The effect is clear at higher temperature. Proper amount of oxidant addition needs to be decided.

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Monoaromatic compounds are important chemicals as raw material for many petrochemical industries. Conventionally, these compounds are obtained from fossil resources by petroleum refining processes. In order to reduce the dependency on this resource, a new route with the utilization of biomass as starting material for the production aromatic chemicals is considered to establish a sustainable system of chemical industry. The route is that acetone could be produced selectively by catalytic reaction from biomass-derived oil. From this point, therefore, this study is to explore a catalytic conversion of acetone toward aromatic chemicals with HZSM-5. The reaction is carried out by continuous flow reactor at an atmospheric pressure to examine the activity and selectivity of HZSM-5. Some parameters such as temperature, space velocity, effect of water have been investigated. The results show that HZSM-5 exhibited a high active and a shape-selective catalyst for the formation of monoaromatic chemicals. The favourable condition for acetone aromatization is found i.e. at 673K with space velocity of 4h^-1, the acetone conversion is close to 100% and monoaromatic selectivity is approximately 71%. The low selectivity of carbon oxides (less than 5%) was obtained, and it could be contributed significantly for this catalytic reaction on realization toward sustainable development of chemical industry in the future. There is no effect of water existence in the acetone feed on the aromatization reaction process, making the process will be simplified.

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