Renewable biomass

Ethanol. From the point of view of availabiUty, ethanol is extremely attractive because it can be produced from renewable biomass. Estimates... 

Wood is one of our most important renewable biomass resources. Unlike most biomass sources, wood is available year round and is more stable on storage than other agricultural residues. In the United States, wood residues from iadustrial by-products totaled 60.8 x 10 metric tons ia 1993 (73). Increasiagly, residues are iacorporated iato manufactured wood products and are used as a fuel, replacing petroleum, especially at wood-iadustry plants (73) some is converted to charcoal but most is used ia the pulp and paper iadustry. Residues are also available for manufacturiag chemicals, generally at a cost equivalent to their fuel value (see Fuels frombiomass Fuels fromwaste). 

Mollersten, K. et al., Efficient energy systems with C02 capture and storage from renewable biomass in pulp and paper mills, Renewable Energy, 29,1583, 2004. 

Facilities using renewable biomass to generate electricity currently produce enough power for about 7 million American households per year.30 Many more biomass generation plants are not on the public power grid, but produce electricity and heat energy for manufacturing operations, primarily in the forest products industry. 

Generating hydrogen from such waste materials may turn out to be one of the least expensive methods of producing hydrogen since this resource is quite extensive. It has been estimated that in the U.S., roughly 14 quads of the annual 64 quad total energy requirement could be met from renewable biomass sources, which is about 20% of our total energy needs. 

Rice straw is a regionally significant low-cost renewable biomass resource. 

We recognize the nuclear reactions of the sun as the main source of our energy and the crucial role of photosynthesis as the conversion process of solar light into fossil energy carriers and renewable biomass. We also recognize gravitational sources that result in tidal movement and the earth s thermal resources. 

Figure 2.1 Renewable biomass (180 billion tons/year).

The catalytic aqueous phase reforming might prove useful for the generation of hydrogen-rich gas from carbohydrates extracted from renewable biomass and biomass waste streams. The biomass-derived hydrocarbons are suitable to hydrogen generation from biomass, as well as for the reforming. 

Ethylene glycol (EG), HOCH2-CH2OH, which is readily available from renewable biomass [280, 281], is an interesting feed molecule for the generation of hydrogen due to its low volatility, which makes it convenient for transport and storage. 

From this step, two options are possible. One is to manufacture bio-based monomers and the other is to use renewable biomass to manufacmre compounds that combine natural products with petro-based Bionolle. This review explains both cases. 

Various nonconventional reaction media have been intensively studied in recent years, including water [34], supercritical COj [35], Jluorous hiphasic [36], and ionic liquids [37] alone or in hquid-liquid biphasic combinations. The use of water and supercritical carbon dioxide as reaction media fits with the current trend toward the use of renewable, biomass-based raw materials, which are ultimately derived from carbon dioxide and water. 

Renewables Biomass utilization Residual and cultivated terrestrial and aquatic biomass can produce liquid or gaseous fuels suitable for the transportation sectors. 

Agricultural crop residues are a valuable renewable biomass resource. In 1999, American farmers harvested 53,909,000 acres of wheat (1). The straw from this acreage of wheat represents >50 million t annually. Currently, some of the straw is harvested (baled) for use as livestock bedding or low-grade animal feed. However, these low-value uses provide only a... 

Carbohydrates, in the form of gums, polysaccharides, oligomers, and monomeric sugars, are readily available in large quanitities from renewable biomass resources. Each of these substances, either directly or in a chemically modified form, is a source of intermediates (derivatives) that have potential use in adhesive formulation. Carbohydrates have been utilized historically for and in adhesives and are likely to be used more and more in the future as petroleum-derived chemicals become scarce and prices increase. Appropriate research emphasis can effectively further their use as adhesive raw material. 

Carbohydrates are readily available from renewable biomass sources. In this introduction, I have given a broad overview of how carbohydrate polymers,... 

Another key topic - renewable resources - is addressed in Chapter 8. The utilization of fossil resources as sources of energy and chemical feedstocks is clearly unsustainable and needs to be replaced by the use of renewable biomass. Such a switch is also desirable for other reasons such as biocompatibility, biodegradability and lower toxicity of the products compared to their oil-derived counterparts. Here again, the application of chemo- and biocatalysis will play an important underlying role. 

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