Alcohol from Wood

ALCOHOL FROM WOOD 1. Add-Digested Wood as a Source of Sugar 

The next attempt to set up a workable scheme for processing wood was made by two chemical engineers who had been associated with Classen. 

It is instructive to consider some of the factors leading to the closing down of the Georgetown and Fullerton plants. In neither case was the shutdown caused by the inoperability of the process as was true of the Classen plant. These plants, operating on sawmill wastes, become useless if the waste has to be transported long distances. Lumber operations follow the forests and have to be moved periodically as timber is cut over. The same requirement applies to alcohol plants attached to lumbering operations. The rate of cutover was so rapid at the Fullerton plant sawmill that it forced a curtailment of operations, which with competition from the low cost molasses process eventually led to the closing of these plants. 

The sulfite process has also been operated in this country following the lead of developments in the Scandinavian countries. Two experimental plants were installed in Sweden in 1907, and United States interest in the development was aroused at once, although no plant was actually built here until 1913, when one was erected at Mechanicsville, Vii nia. This plant was put into operation by Ekstrom, who developed the Swedish process. It was a modern installation with a capacity of 6500 gal. of alcohol per day. The fermentation tanks were made of steel. Liquor from the 

As a concluding statement to this survey one cannot do better than to quote from the excellent summary by Sherrard and Kressman (119), from which most of the above information was taken  

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The early sources of phenol were the destructive distillation of coal and the manufacture of methyl alcohol from wood. In both cases, phenol was a by-product. Recovered volumes were limited by whatever was made accidentally in the process. Initial commercial routes to on-purpose phenol involved the reaction of benzene with sulfuric acid (1920), chlorine (1928), or hydrochloric acid (1939) all these were followed by a subsequent hydrolysis step (reaction with water to get the -OH group) to get phenol. These processes required high temperatures and pressures to make the reactions go. They re multistep processes requiring special metallurgy to handle the corrosive mixtures involved. None of these processes is in commercial use today. 

Methylamine occurs in herring brine 2 in crude methyl alcohol from wood distillation,3 and in the products obtained by the dry distillation of beet molasses residues.4 It has been prepared synthetically by the action of alkali on methyl cyanate or iso-cyanurate 5 by the action of ammonia on methyl iodide,6 methyl chloride,7 methyl nitrate,8 or dimethyl sulfate 9 by the action of methyl alcohol on ammonium chloride,10 on the addition compound between zinc chloride and ammonia,11 or on phos-pham 12 by the action of bromine and alkali on acetamide 13 by the action of sodamide on methyl iodide 14 by the reduction of chloropicrin,15 of hydrocyanic or of ferrocyanic acid,16 of hexamethylenetetramine,17 of nitromethane,18 or of methyl nitrite 19 by the action of formaldehyde on ammonium chloride.20... 

In contrast to the Western economy, the Russia continued expansion of wood hydrolysis facilities, and about 40 such plants are presently in operation. All the Russian plants are based on dilute sulfuric acid in percolation towers. In the West interest in producing alcohols from wood was revitalized by the dramatic increase in the price of petroleum in the 1970s and the push to decrease oil imports by substituting gasohol, which is one part alcohol in nine parts gasoline, for 100 percent gasoline at gas pumps. Both ethanol and methanol can be used in gasohol blends. 

In some preliminary experiments concerning the manufacture of ethyl alcohol from wood waste, F. W. Kressman described a process as follows The process of producing ethyl alcohol from wood consists, in (general, of digesting sawdust or hogged and shredded wood with a dilute mineral acid at from 60 pounds and more, of steam pressure. This converts part of the wood into a mixture of pentose and hexose sugars. The latter are then fermented, producing alcohol. 

Manufacture of Industrial Alcohol from Wood Pulp Liquor. 

The processes used for the production of ethyl alcohol from wood may be grouped into two general classes Hydrolysis of wood into fermentable sugars by the use of dilute acid (preferably mineral acid) aB a catalyzer, and solution processes, in which the wood is dissolved in concentrated acid and the diluted solution is then subjected to hydrolysis. 

Sharkov VI. Production of polyhydric alcohols from wood polysaccharides. Angew Chem hit Ed 1963 2 405-9. 

Until the 1920s the major source of methanol was as a byproduct m the production of charcoal from wood—hence the name wood alcohol Now most of the more than 10 billion lb of methanol used annually m the United States is synthetic prepared by reduc tion of carbon monoxide with hydrogen... 

Aoyama, W. Sasaki, S. Matsumura, S. Mitsunaga, T. Hirai, H. Tsutsumi, Y. Nishida, T. Sinapyl alcohol-specific peroxidase isoenzyme catalyzes the formation of the dehy-drogenative polymer from sinapyl alcohol. J. Wood Sci. 2002, 48, 497-504. 

Methyl alcohol, CH2OH, also called wood alcohol or wood spirit, since it was formerly obtained from the destructive distillation of wood. It has also been synthesised from carbon monoxide and hydrogen or by fermentation of various sugar containing crops. Used as a part replacement for petrol in Gasohol to deliver a more environmentally friendly fuel, i.e., from renewable resources. 

There s a good reason why methanol is commonly called wood alcohol. The early commercial source was the destructive distillation of the fresh-cut lumber from hardwood trees. When wood is heated without access to air at temperatures above 500°F, it decomposes into charcoal and a volatile fraction. Among the compounds in the volatile fraction is methanol. Hence, the name wood alcohol or wood spirits. 

Before 1920s, methanol was obtained from wood as a co-product of charcoal production, hence the name wood alcohol. Methanol is currently manufactured worldwide from syngas, which is derived from natural gas, refinery off-gas, coal or petroleum, as ... 

Biorefinery includes fractionation for separation of primary refinery products. The fractionation refers to the conversion of wood into its constituent components (cellulose, hemicelluloses and lignin). Processes include steam explosion, aqueous separation and hot water systems. Commercial products of biomass fractionation include levulinic acid, xylitol and alcohols. Figure 3.3 shows the fractionation of wood and chemicals from wood. 

Lourith N, Katayama T, Ishikawa K et al (2005) Biosynthesis of a syringyl 8-0-4 neoUgnan in Eucommia ulmoides formation of syringylglycerol-8-0-4 -(sinapyl alcohol) ether from sinapyl alcohol. J Wood Sci 51 379-386... 

Interest in renewable resources as raw materials for chemicals and energy has intensified in recent years as a result of anticipated shortages of petroleum and natural gas ( 1, 2, 3). A significant part of this effort has been devoted to the production of alcohols, particularly methanol and ethanol, from wood ( - ) Methanol is the main constituent of "wood alcohol", made for a great many years by the destructive distillation of wood, especially hardwoods W. From a ton of hardwood, one could expect about 60 lb, that is 7.5 gallons of methanol, along with a variety of other chemicals. Wood alcohol is no longer made. The processes discussed in recent reports, are quite different,... 

Alcohol recovery from the fermentation brews was less than complete in most cases, which may be attributable to less than ideal conditions. The best yields, 60 to 97% of theory, were obtained with sugars obtained by hydrolysis of cellulosic residues of the autohydrolysis-extraction process. Unextracted pulps, or the hemicellulose solutions, gave poor ethanol formation, which suggests inhibition. In the calculation of material and energy balances which follows, we have assumed 95% yields of ethanol from wood sugars, which is readily achieved in industrial practice and which we believe to be achievable with our wood sugars as well. 

A number of lower volume chemicals can be obtained from wood hydrolysis. Furfural is formed from the hydrolysis of some polysaccharides to pentoses, followed by dehydration. This process is still used in the Soviet Union. Furfural is used in small amounts in some phenol plastics it is a small minor pesticide and an important commercial solvent. It can be converted into the common solvent tetrahydrofuran (THF) and an important solvent and intermediate in organic synthesis, furfuryl alcohol. 

The pentose sugars, as well as the hexoses, are utilized by acetone-and butyl alcohol-producing organisms. Partansky and Henry reported the production of butanol and acetone from wood sugars. This work was continued in the laboratory of W. H. Peterson of the University of Wisconsin. Tables VIII and IX summarize their findings with two organisms. 

Holocellulose Cellulosic material obtainable from wood after removal of lignin. The term therefore means total carbohydrates (cellulose and hemicellulose) present in the wood (Refs 1 2) Ritter (Ref 3) succeded in isolating holocellulose from wood pulp by repeated chlori-nations, followed by extraction with alcohol containing 3% of monoethanolamine. The resulting product was white but changed color on standing... 

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