Phenol from lignin

All of the studies mentioned are directed to lignins derived from pulp and paper manufacture. This requires that a traditionally conservative pulp and paper industry embark on further development as a chemical producer. However, Helena Chum and her colleagues (Chapter 11) derive their phenolics from lignin by fast pyrolysis of wood rather than as byproducts from the pulp and paper industry. Opportunities might be better for development of adhesives from a chemical manufacturer drawing on waste wood as a raw material much the same as has developed in the production of furan resins derived from agricultural residues described by Bill McKillip (Chapter 29). 

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

Yoshikawa T, Yagi T, Shinohara S, Fukunaga T, Nakasaka Y, Tago T, Masuda T (2013) Production of phenols from lignin via depolymerization and catalytic cracking. Fuel Process Technol 108 69... 

Figure 3.60 shows the hydrocracking process developed by Hydrocarbon Research to produce phenols from lignin. 

Mixing vessel 2 Hydrogenation reactor 3 Gas separator 4 Distillation column Figure 3.60 Flow diagram for recovering phenol from lignin HRI)... 

G. Kakemono, H. Sagara, N. Suzuki and S. Kachi, Method of manufacturing phenols from lignin, US Patent 4900873, assigned to JGC Corporation and Japan Pulp Paper Research Institute, Inc., February 13,1990. 

Other C6-based building blocks are uhlized at scales above 100 kton/year. Sorbitan (formed by the dehydration of sorbitol), ascorbic acid (formed by a combined biotechnological/ chemical process), and phenols (from lignin) are some important examples (Jong, 2012). 

Dynaphen A process for converting mixed alkyl phenols (from coal liquids or lignin) to benzene, phenol, and fuel gas, by noncatalytic hydrogenation at high temperature. Developed and offered by Hydrocaibon Research. 

The fungal enzyme from R. praticola was able to catalyze the oxidative coupling of pentachlorophenol (PCP) and syringic acid, a representative of phenol carboxylic acids from lignin occurring in HS structures. 

Mn-dependent peroxidase differs from lignin peroxidase in that it utilizes Mn (II) as the main substrate (74). The oxidized manganese ion, Mn (III), carries out the oxidation of organic molecules. Compound I of Mn-dependent peroxidase is able to oxidize Mn (II) to Mn (III) as well as some phenolic compounds the compound II can only oxidize Mn (II) (14) ... 

P. chrysosporium and abstracts electrons from lignin substructures with lower redox potentials such as phenolic units. The enzyme directly oxidised Mn II to Mn III as the initial step in lignin attack. Other enzymes... 

Various attempts have been made to prepare adhesives from lignin. The preparation of resol resin adhesives has been studied especially extensively. The introduction of phenols into the a or /2-position of the sidechain of the phenylpropane unit (phenolation of lignin) has been considered a key reaction for the formulation of these types of adhesives with adequate glu-ability. 

Epoxy resin adhesives from lignin were reported by Tai et al. (19,20) in 1967. Satisfactory gluability was found. The solubility in organic solvents, however, was found to be poor. In essence, the phenolic hydroxyl groups of kraft lignin were glycidylated directly. 

There have been many attempts to prepare resol resin adhesives from kraft lignin (23). Phenolation of lignin can, in these cases, also be considered a key reaction. That is, effective modification of lignin with phenol can enhance its reactivity, resulting in good gluability. 

Vanillin, syringaldehyde, and related phenolic products derived from lignin appear to be important in the desirable odor contributed to beverages by oak barrels (25, 26, 27). These substances are present in the wood, but more appears in the beverage than simple extraction seems to allow. Also the odor of vanillin seems to increase with time and mellowing of the beverage compared with a fresh extract of new wood (25). 

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