Lignocellulose transformation

Second-generation biofuel technologies make use of a much wider range of biomass feedstock (e.g., forest residues, biomass waste, wood, woodchips, grasses and short rotation crops, etc.) for the production of ethanol biofuels based on the fermentation of lignocellulosic material, while other routes include thermo-chemical processes such as biomass gasification followed by a transformation from gas to liquid (e.g., synthesis) to obtain synthetic fuels similar to diesel. The conversion processes for these routes have been available for decades, but none of them have yet reached a high scale commercial level. 

Telysheva, G., Dobele, G., Meier, D., Dizhbite,T., Rossinka, G., and Jurkjane, V. (2007). Characterization of the transformation of lignocellulosic structures upon degradation in planted soil. J. Anal. Appl. Pyrolysis 79, 52-60. 

Moreover, lignocellulose is not edible and could theoretically be utilized without any impact on food production. The cellulose and hemicellulose fraction of lignocellulose may serve for the production of cellulosic ethanol, which could be produced via acid or enzymatic catalyzed hydrolysis of cellulose, followed by further fermentation to yield ethanol. Alternatively, the whole plant can be gasified to yield syngas, followed by methanol or dimethyl ether synthesis or Fischer-Tropsch technology that produces hydrocarbon fuels. Furthermore, controlled (bio-)chemical transformations to novel fuel compounds based on cellulose, hemicellulose, or lignin are possible, and numerous recent publications emphasize intense research in this direction. 

Schoning AG, Johansson G (1965) Absorptiometric determination of acid-soluble lignin in semichemical bisulfite pulps and in some woods and plants Sven Papperstidn 68 607-613 Schultz TP, Templeteon MC, McGinnis GD (1985) Rapid determination of lignocellulose by diffuse reflectance Fourier transform infrared spectrometry Anal Chem 57 2867- 2869 Sjostrom E, Enstrom B (1966) Spectrophotometnc determination of the residual lignin in pulp after dissolution in cadoxene Sven Papperstidn 69 469-476... 

Grandmaison JL, Thibault J, Kaliaguine S, Chantal PD (1987) Fourier transform infrared spectrometry and thermogravimetry of partially converted lignocellulosic materials Anal Chem 59 2153-2157... 

Stofko, J. L. Carbohydrate Transformation Bonding of Lignocellulosic Materials, paper presented at the Wood Adhesive-Research, Application and Needs Symposium, Madison, WI, 1980. 

Utilization of wood-biomass residues as well as waste polymers is the important direction of recent research activities. It is known that direct catalytic liquefaction of plant biomass can be used to produce liquid fuels and chemicals [1,2]. Co-pyrolysis and co-hydropyrolysis processes have the potential for the environmentally friendly transformation of lignocellulosic and plastic waste to valuable chemicals. 

Nitric Acid and Nitrate Activation. The reactions of HNO3, nitrates, and nitrogen oxides with lignocellulosic materials have been a subject of numerous publications. The specific transformations can be subdivided into acid reactions, oxidation reactions, and nitration-esterification reactions. With HNO3 and more acidic salts the acid reactions predominate at higher dilutions, and parallel those of aqueous solutions of H2SO4 and other similar acids. Oxidation of cellulose results primarily in oxidation of primary hydroxyls to carboxyls, with the secondary hydroxyls oxidized less. Nitration leads... 

Despite the variety of sources, all lignocellulosic material is composed primarily of cellulose, hemicellulose and lignin [22], Agricultural wastes such as bagasse, com stover and wheat straw are thus a relatively cheap source of these three biopolymers. The major challenge to using lignocellulosic biomass as a feedstock is the development of cost-effective methods to separate, refine and transform it into chemicals and fuels [20],... 

TP Schultz, MC Templeton, and GD McGinnis. Rapid Determination of Lignocellulose by Diffuse Reflectance Fourier Transform Infrared Spectrometry. Anal. Chem. 57 2867-2869, 1985. 

The development of an economic process for increasing the digestibility of these lignocellulosic materials should provide for disposal—in a useful manner—of large quantities of coarse fibrous materials. This type of process would provide the medium through which these coarse unused plant tissues would be transformed into protein-rich food supplements for human consumption. 

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