Lignin in biomass

Templeton, D. and Ehrman, T. (1995), Determination of acid-insoluble lignin in biomass, in Laboratory Analytic Procedure LAP-003, National Renewable Energy Laboratory, Golden, CO. 

Com stover used for this study was harvested in 2003 at the Kramer Farm in Wray, Colorado. The stover was pretreated either in-house at the National Renewable Energy Laboratory or received via subcontract fiom the CAFI [12] pretreatment group members. The samples selected for this study were pietreated by alkaline peroxide (NREL), sulfite steam explosion (UBC), ammonia fiber explosion (MSU), and dilute sulfuric acid (NREL) methods. The composition of the pretreated stover was determined by a two-stage sulfuric acid hydrolysis treatment according to the NREL Laboratory Analytical Procedure titled Determination of Stmctural Carbohydrates and Lignin in Biomass [13]. The pretreatment conditions and compositional information for each substrate are listed in Table 2. 

Sluiter, A., Hames, B., Ruiz, R., Searlata, C., Sluiter, J., Templeton, D.(2004). Determination of structural carbohydrates and lignin in biomass, DOE, Editor. National Renewable Energy Laboratory. 

Composition analysis of the treated/untreated biomass was done according to the NREL Laboratory Anal)dieal Procedures Preparation of samples for compositional analysis and determination of structural carbohydrates and lignin in biomass (draft version) [32]. The moisture content in biomass was measured by an inftared moisture balance (Denver Instrument, IR-30). Sugar content in compositional analysis and enzymatic digestibility was determined by HPLC using a Bio-Rad Aminex HPX-87P. 

Vanholme R, Morreel K, Darrah C, Oyarce P, Grabber JH, Ralph J, Boerjan W (2012) Metabolic engineering of novel lignin in biomass crops. New Phytologist 196 978... 

Supercritical fluid solvents have been tested for reactive extractions of liquid and gaseous fuels from heavy oils, coal, oil shale, and biomass. In some cases the solvent participates in the reactions, as in the hydrolysis of coal and heavy oils with water. Related applications include conversion of cellulose to glucose in water, dehgnincation of wood with ammonia, and liquefaction of lignin in water. 

In addition to the normally suggested, sample pre-treatment procedures used prior to l.c. injection to avoid column contamination, Cig bonded silica-gel cartridges are particularly useful for removal of lignin-derived degradation-products that occur in biomass-conversion samples. 

Soluble and insoluble lignin were determined with the NREL standard biomass analytical methods for the analysis of acid-insoluble and acid-soluble lignin inbiomass, LAP-003 and LAP-004, respectively (13-14). NREL s laboratory analytical procedure for the determination of carbohydrates in biomass, LAP-002, without correction for hydrolysis losses was performed to determine the sugar content (15). 

As reported in the U.S. Department of Energy study Top Value-Added Chemicals from Biomass. Vol. II, Results of Screening for Potential Candidates from Biorefinery Lignin, the biomass production in the United States is capable of supplying all necessary raw materials for the complete chemical industry [17]. 

Chen C L, Robert D (1988) H and nC NMR spectroscopy of lignin In Wood WA, Kellogg ST (eds) Methods in enzymology biomass, Part B, Vol 161 Academic Press, New York, 137-174... 

Pecma R, Burtscher P, Bonn G, Bobleter O (1986) GC-MS and HPLC analyses of lignin degradation products in biomass hydrolyzates Fresenius Z Anal Chem 325 461-465... 

Lin, S. Y. Lignin Utilization Potential and Challenge In Progress in Biomass Conversion, Academic Press, Inc. Orlando, 1983 Vol. 4, 31-78. 

Flash pyrolysis in FFR is a usefnl means to remove snlphnr from coal [19, 21]. As shown by Li et al. [22], it can also be ntilized to remove heteroatom molecules from biomass. Both the yield and the composition of the resnltant gas depend on the biomass composition. The gas ontpnt is richer in hydrogen in the case of cellulose and hemicel-Inlose than in the case of lignin. Smaller biomass particle sizes and higher fast pyrolysis temperatnres also boost hydrogen content. The total of carbon monoxide and hydrogen content is reported to be 65.4% for legnme straw and 55.7% for apricot stone. 

Minami, E., Kawamoto, H., Saka, S. (2002). Reactivity of lignin in supercritical methanol studied with some lignin model compoimds. In "12 European Biomass Conf.", pp. 785—788. ETA Firenze WIP Munich. 

A short discussion is also in order regarding the biochemical pathways to the polysaccharides (celluloses and hemicelluloses), which are the dominant organic components in most biomass, and the lignins, proteins (polypeptides), and triglycerides (lipids or fats) that are found in biomass. Most biomass on... 

As previously mentioned, the triglycerides found in biomass are esters of the triol, glycerol, and fatty acids (Fig. 3.6). These water-insoluble, oil-soluble esters are common in many biomass species, especially the oilseed crops, but the concentrations are small compared to those of the polysaccharides and lignins. Many saturated fatty acids have been identified as constituents of the lipids. Surprisingly, almost all the fatty acids that have been found in natural lipids are straight-chain acids containing an even number of carbon atoms. Most lipids in biomass are esters of two or three fatty acids, the most common of which are lauric (Cn), myristic (Cu), palmitic (Cia), oleic (Cis), and linoleic (Cis) acids. Palmitic acid is of widest occurrence and is the major constituent (35 to 45%) of the fatty acids of palm oil. Lauric acid is the most abundant fatty acid of palm-kemel oil (52%), coconut oil (48%), and babassu nut oil (46%). The monounsaturated oleic acid and polyunsaturated linoleic acid comprise about 90% of sunflower oil fatty acids. Linoleic acid is the dominant fatty acid in com oil (55%), soybean oil (53%), and safflower oil (75%). Saturated fatty acids of 18 or more carbon atoms are widely distributed, but are usually present in biomass only in trace amounts, except in waxes. 

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