Production of high purity hydrogen from biomass/wood by catalyst-enhanced and reaction-integrated supercritical water gasification

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Hydrogen (H2), the fuel of the future, is the cleanest fuel with zero emission of air-pollutants during combustion. Its demand is continuously growing especially in the oil refining, ammonia production and fuel cells industries. Currently, H2 is produced mainly from conversion of non-renewable fossil fuels (natural gas) by steam reforming at high temperatures (800-1,000°C) with a high production cost, approximately 5 times the cost of the hydrocarbon used. Fossil fuels are non-renewable, expensive and the use of fossil fuels is seriously damaging to the global environment with emissions of SO2, NOx and the greenhouse gas (CO2). Thus producing H2 from biomass (the renewable energy resource) is very promising, as a cost-effective and environmentally friendly process with zero net CO2 emission.     This project aims at developing a novel Catalyst-Enhanced and Reaction-Integrated Supercritical Water Gasification (CERI-SCWG) process for production of high purity H2 from biomass/wood energy resources (including wood barks, wood chips, sawdust and the solid waste from pulp mills) at much lower temperatures (400-600°C). To develop such a technology to produce H2 would be strategically significant for Canada which has the world's most abundant wood biomass energy resources, from both environmental and economic points of view. In a conventional biomass/coal steam gasification process, the overall reaction is highly endothermic and equilibrium limited. In order to achieve a high conversion of carbon, high temperature (800-1,200°C) is required, leading to high energy-consumption and hence high production cost. Supercritical water (SCW) has unique solvating and transport properties, and in particular has the ability to dissolve materials not normally soluble in liquid water or steam, which thus favor the gasification reactions. If using SCW instead of steam, efficient conversion of biomass to hydrogen under much lower temperature may be achievable. Another novelty of the project is to further boost the gasification reactions kinetically and thermodynamically by employing catalysts and CO2 adsorbents.