Biomass derivatives

Eig. 14. Primary biomass-derived chemicals. Dominant processiag methods are chemical (C), fermentation (E), enzymic (E), and natural (N) processes ... 

A bleached kraft pulp mill requires 15,140 to 45,420 L (4000 to 12,000 gal) of water and 8.56 to 12.22 million chu (14 to 20 million Btu) of energy per ton of pulp, of which ca. 4.44 to 5.56 million chu (8 to 10 million Btu) are typically derived from biomass-derived fuel from the pulping process itself.4 Across all facilities, the pulp, paper, and allied products industry is the largest consumer of process water and the third largest consumer of energy (after the chemicals and metals industries).5,6 The large amounts of water and energy used, as well as the chemical inputs, lead to a variety of environmental concerns. 

Hydrogen from Biomass-Derived Other Intermediates.213... 

Hydrogen Production from Biomass-Derived Methanol.213... 

Hydrogen Production from Other Biomass-Derived Oxygenates.214... 

Widely differing processes have been reported for hydrogen production based on biomass-derived intermediate compounds. Some of the main ones are reported in this section. 

Currently, there is renewed interest in this process. At Twente University (The Netherlands), research is performed toward the use of bio-oil from (flash) pyrolysis as the reducing agent for the oxidized iron.149 Therefore, a CO-containing gas stream and a relatively pure H2 stream is generated separately from the biomass-derived bio-oil. 

Mudge, L. K. Baker, E. G. Brown, M. Wilcox, W., Catalytic destruction of tars in biomass-derived gases. In Research in Thermochemical Biomass Conversion, Bridgwater, A. V. Kuester, J. L., Eds., Elsevier Applied Science, London, 1988, pp. 1141-1155. 

Spath, P. L. Dayton, D. C., Preliminary Screening—Technical and Economic Assessment of Synthesis Gas to Fuels and Chemicals with Emphasis on the Potential for Biomass-Derived Syngas. NREL/TP-510-34929 NREL, Golden, CO, 2003. 

Takanabe, K. Aika, K.-I. Inazu, K. T. B. Seshan, K. Lefferts, L., Steam reforming of acetic acid as a biomass derived oxygenate Bifunctional pathway for hydrogen formation over Pt/ZrOz catalysts. Journal of catalysis 2006,243(2), 263-269. 

Huber, G. W. Chheda, J. N. Barrett, C. J. Dumesic, J. A., Production of liquid alkanes by aqueous-phase processing of biomass-derived carbohydrates. Science 2005, 308(5727), 1446-1450. 

Cortright, R. D. Davda, R. R. Dumesic, J. A., Hydrogen from catalytic reforming of biomass-derived hydrocarbons in liquid water. Nature 2002,418,964. 

Bakhshi, N.N., Dalai, A.K, and Srinivas, S.T. (1999). Conversion of Various Biomass-derived Chars to Hydrogen/High Btu Gas by Gasification with Steam, Proceedings of the 4th Biomass Conference of the Americas, Oakland, CA, August 29-September 2, 1999. pp. 985-990. 

Srinivas, S.T., Dalai, A.K., and Bakhshi, N.N. (1998). Potential of Producing Hydrogen and High Btu Gas from Steam Gasification of Biomass-derived Chars, Canadian Society for Chemical Engineering Conference, London, Canada, 4-7 Oct CONF-981052(ISBN 0-920804-32-2). 

Scheme 1 Carbon cycle energy diagram for the production of H2 from biomass-derived ethanol.18...

In the case of biomass-derived fuels, the C02 emitted by carbon-containing fuels is absorbed from the atmosphere during the growth of the plants. As a result, the combustion of biomass-derived fuels is assumed to be C02 neutral at a global scale. 

With carbon-containing biomass-derived fuels, well-to-tank (WTT) GHG emissions are negative because the carbon bound in the fuel is removed from the... 

Among liquid fuels (XTL), only biomass-derived hydrocarbons (BTL) are a relevant option from the perspective of lowering GHG emissions not so other fossil-based liquids (CTL, GTL). Even if CTL fuel supply paths were upgraded by carbon capture and storage, the resulting specific CCF-equivalent emissions would only be reduced to the level of conventional gasoline or diesel energy chains. 

The additional and steadily increasing demand for biofuels could lead to a situation where production of biomass derived fuels finally compete with food production. People who can afford cars can pay more for biomass for fuels than people in non-industrialised countries can pay for food production. Fertile soil in non-industrial countries might then be used for energy crops instead of food. This may eventually lead to a situation where only bad soil is left for food crops and the poor, which in addition would eventually also lead to further deforestation of the World s rainforests. 

The European Commission wants to have a contribution of 12% energy from renewable sources to the energy budget within the EC in 2010. The relative amount of bio-fuels will increase to a level of 5.75%, this is more than twice the corresponding use of oil. The US Department of energy has set goals to replace 30% of the liquid petroleum transportation fuels with biofuels and to replace 25% of industrial organic chemicals with biomass-derived chemicals by 2025 [7]. 

The potential of combining a lower need for deoxygenation and a higher product value is illustrated in Fig. 2.15. It shows that the selective incorporation of oxygen into a hydrocarbon, as done in the petrochemical industry, is very expensive. In contrast, the bio-based alternative enjoys two advantages. Firstly, the feedstock is cheaper than crude oil, even on an energy and carbon base, as discussed above. Secondly, its selective deoxygenation has been proven to cheaper than the petrochemical route in a few cases, e.g., for ethanol and furfural. The same can be expected for other biomass derivates in the future. 

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