Biomass conversion hydrogen production

A variety of chemical and biological reactions involving supercritical fluid technology are being explored and developed. They include polymerization reactions, biomass conversion, hydrogen production, applications of supercritical water oxidation, self-assembly applications, synthesis of specialty chemicals, manufacture of materials with tailored properties, and much more. These developments and new ones are expected to mature and be commercially deployed in years to come. 

This review limits itself to the treatment of high-temperature thermochemical biomass conversion technologies. There are very good overviews of biological conversion technologies for hydrogen production, for example, Ni et al.13 and Zaborsky.29... 

Biollaz, S. Sturzenegger, M. Stucki, S., Redox Process for the production of clean hydrogen from biomass. In Progress in Thermochemical Biomass Conversion, Seefeld, Tirol, 2000. 

Chaudhari, S.T., Ferdous, D., Dalai, A.K, Bej, S.K, Thring, R.W., and Bakhshi, N.N. (2000). Pyrolysis and Steam Gasification of Westvaco Kraft Lignin for the Production of Hydrogen and Medium Btu Gas, Abstracts Progress in Thermochemical Biomass Conversion, Tyrol, Austria, 17-22 September. 

Biomass combustion devices, 3 686-688 Biomass conversion, for hydrogen production, 73 784... 

The production of H2 from some by-products of biomass conversion is also a possible option, which also requires the development of, new, more stable, more efficient catalysts that operate directly in the liquid phase. The catalytic production of hydrogen from more valuable products, such as bioethanol, should be reconsidered with appropriate economic assessments that take into account the alternative possible uses of these products. 

Although technologies have been developed over past 50 years to process petroleum-based feedstock efficiently to generate hydrogen, its production from rene v-able biomass-derived resources remains a major challenge, because conversion processes often suffer from low hydrogen production rates and/or complex processing requirements [24, 25]. 

Another promising route for hydrogen production via biomass is gasification. Biomass gasification is done in the presence of oxygen and steam. The conversion process can be represented as... 

Earlier studies have been done by pure cultures of anaerobic bacteria to study the conversion of carbohydrates (such as glucose and starch) to hydrogen gas, e.g., Aspergillus terreus (Emtiazi et al., 2001) and Clostridium (Taguchi et al., 1994). Recently, the considerable attention of research activity on fermentative hydrogen-production has been focused on the conversion of biomass reproducible resources to hydrogen by mixed cultures... 

Coproduction (biorefinery) of, for example, phenolic adhesives, polymers, waxes, and other products with hydrogen production from biomass is being discussed in the context of biomass gasification plant designs to improve the overall economics of biomass-to-hydrogen conversion.11 The technical and economic viability of such coproduction plants is unproven and was not considered in this analysis. 

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