Lignocellulose thermochemical conversion

Industrialbiobased products have enormous potential in the chemical and material industries. The diversity of biomass feedstocks (sugars, oils, protein, lignocellulosics), combined with the numerous biochemical and thermochemical conversion technologies, can provide a wealth of products that can be used in many applications. Targeted markets include the polymer, lubricant, solvent, adhesive, herbicide, and pharmaceutical markets. Industrial bioproducts have already penetrated some of these markets, but improved technologies promise new products that can compete with fossil-based products in both cost and performance. 

Foust, T.D., Aden, A., Dutta, A., Phillip, S. (2009). An economic and environmental comparison of a biochemical and a thermochemical lignocellulosic ethanol conversion processes. Cellulose, 16, 547-565. 

The present chapter discusses aspects, known by the authors, of (a) biomass as feedstock, (b) the concept of bio-refinery, (c) thermochemical routes from lignocellulosic biomass to fuels, and (d) the contribution of catalytic technology. The main focus will be on the catalytic conversion of fast pyrolysis oil into fuels with regard to problems encountered currently and the challenges for future research and development. 

Basically, there are three thermochemical routes (Fig. 6.4) for the conversion of lignocelluloses into fuels ... 

Conversion efficiency and robust fermentation of mixed-sugar lignocellulose-derived hydrolysates are critical for producing ethanol at low cost to realize a commercially viable biorefinery. Biomass sugars are typically released by thermochemical pretreatment followed by enzymatic hydrolysis of chopped or milled biomass. The pretreated soluble fraction of biomass is called the hydrolysate and the hydrolysate containing the insoluble... 

When perfected, synthesis-gas-to-ethanol technology can be expected to have a large impact on fermentation ethanol markets. It is likely that thermochemical ethanol would then be manufactured at production costs in the same range as methanol from synthesis gas, which can be produced by gasification of virtually any fossil or biomass feedstock. Applying the advances that have been made for conversion of lignocellulosic feedstocks via enzymatically catalyzed options, it has been estimated that the production cost of fermentation ethanol... 

In diis chapter, the main technical aspects of different thermochemical processes for biomass conversion are discussed. In addition, various hydro-thermal treatments applied to lignocellulosic biomass for the production of fermentable sugars, hydrogen or other value-added products are presented. This chapter also describes about pyrolysis along with its various parameters that influence conversion product yields. Bio-oil, which is a complex mixture or both aqueous and organic biomass components, is discussed in details along with its catalytic upgrading for use as transportation fuel. 

Several other materials are also produced in maize and a fairly high amount of solar energy is trapped in unused lignocellulosic stover. Ongoing studies are focused on the development of enzymatic biocatalyst and/or thermochemical processes to utilize lignocellulosic biomass, with improved conversion into energy or into molecular building blocks such as levulinic acid [361]. 

Dutta, A., Takaadge, M., Hensley, J. et al. (2011) Process Design and Economics for Conversion of Lignocellulosic Biomass to Ethanol Thermochemical Pathway by Indirect Gasification and Mixed Alcohol Synthesis, NREL/TP-5100-51400. Available at http //www.nrel.gov/biomass/pdfs/51400. pdf (accessed on 29 August 2015). 

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