Lignocellulosic residues lignin

Lignocellulosic residues Lignin (%) Hemicellulose (%) Cellulose (%) Reference... 

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... 

The GC internal standard is usually hexacosane (C26) and/or tetracosane (C24) For complex samples, such as those represented by lignocellulose residues, it is advisable to add both of these internal standards The amount of each internal standard (C26 and/or C24) to be added is 0 5 mg/20 mg of extractive-free wood, 0 25mg/20mg of extractive-free straw, and lmg/5mg of milled wood lignin (Note 6)... 

Silylation the final CH2C12 solution of the thioacidolysis sample is again carefully dried over Na2S04, 5-10/d of this dried organic solution is trimethylsilylated (TMS) at room temperature with 50/i of N,0 bis (trimethylsilyl) trifluoroacetamide (BSTFA) and 5 1 of GC-grade pyridine in a 200-/d reaction vial fitted with a Teflon-lined screwcap For soluble lignin samples, the silylation is complete within a few minutes, for lignocellulose residues, silylation is complete within 2 to 4h In both cases and with well-dried samples, silylations performed in the aforementioned vials are stable for several days (at least 48 h)... 

The fraction consisting of cellulose and hemicellulose or, in other words, the set of all carbohydrates in a lignocellulosic material, is also called holocellulose. Thus, holocellulose is the product obtained after selective removal of lignin, with very low residual-lignin content, minimal loss of polysaccharide, and minimal oxidative and hydrolytic degradation of cellulose. The a-cellulose is the part of material that is insoluble in strong NaOH (17.5%) and may also be designated by crystalline cellulose [5]. In this work, the values of holocellulose and a-cellulose are also shown in Table 1. 

Lignocellulose biomass is a mixture of phenolic lignin and carbohydrates -cellulose and hemi-cellulose. It grows abundantly on earth and is largely available as agricultural and forestry residues. Lignocellulose can be converted via four major routes pyrolysis, gasification, hydrolysis and fermentation. 

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