Phenols lignin pyrolysis

Table 4.7.1. Retention times of phenolic lignin pyrolysis products relative to guaiacol (1 0) separated on columns with differing liquid phases...

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. 

Table 4.7.1 lists phenolic lignin-derived pyrolysis products according to their relative retention times on DB-1701 (0.25- and 1.0-//m films) and DB-5 (0.25-pm films) quartz capillary columns. 

Phenolic and Lignin Pyrolysis Products of Plants, Seston, and Sediment in a Georgia Estuary... 

Recently, SOM has begun to be analyzed by pyrolysis, which is destruction at high temperatures in the absence of oxygen, and analysis of the many volatile compounds that emanate from SOM. Carbohydrates, phenols, lignin and n-fatty acids are the... 

They also demonstrated that the major volatile phenols (phenol, cresols) were produced primarily by pyrolysis of the alcohol extractable and the final tobacco residue. These fractions acconnted for 38% and 44%, respectively, of the total phenols yield. The alcohol extractables included polyphenolic tobacco pigment and low molecular weight sugars, whereas the final tobacco residue contained the polysaccharides celluloses, starch, pectins, and lignin. All these yield the simple phenols on pyrolysis or during tobacco smoking (248, 2043, 3277, 3305, 3453, 3468, 3767). 

In 1979, Martin et al. (2468a) not only reported the results of their own research on the generation of a variety of phenols during the pyrolysis of lignin derived from several sources but also reviewed the results of their own and earlier studies by other investigators on lignin pyrolysis. 

Mante OD, Rodriguez JA, Babu SP (2013) Selective defunctionalization by Ti02 of monomeric phenolics from lignin pyrolysis into simple phenols. Bioresour Technol 148 508... 

As to the origins of the major N compounds identified, it is possible that at least a portion of some of these compounds are pyrolysis products of amino acids, peptides, proteins, [18] and porphyrins (a component of chlorophyll), [19] or originate from the microbial decomposition of plant lignins and other phenolics in the presence of ammonia. [20] Of considerable interest are the identifications aromatic and aliphatic nitriles. Nitriles can be formed from amines with the loss of 2 H2, from amides with the loss of H20, and also by reacting n-alkanoic acid with NH3. [21] The detection of long-chain alkyl- and dialkyl-nitriles points to the presence in the soil or SOM of long-chain amines... 

Lignin-derived compounds have been observed in pyrolysis products of low rank coals and associate woody tissue FI- 61. Mycke and Michaelis [2] isolated lignin-derived methoxyphenols from a Miocene coal by catalytic hydrogenolysis. Sigleo [S] reported the presence of phenolic compounds derived from iteration of lignin in pyrolysis products of silicified woody tissue as old as Triassic age. However,... 

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