Weizmann process

Microorganisms have also been developed to produce alternative products, such as lactic acid [65], propane-1,3-diol [67], 3-hydroxypropionic acid [68], butane-2,3-diol [69] and numerous other intermediates. For instance, bacteria such as the Clostridium acetobutylicum ferment free sugars to C4 oxygenates such as butyric acid or butanol. They form the C4 oxygenates by Aldol condensation of the acetaldehyde intermediates. The Weizmann process exploits this property to ferment starch feedstock anaerobically at 37 °C to produce a mixture of w-butanol, acetone and ethanol in a volume ratio of 70 25 5 [3],... 

The C4 aldol intermediate of the Weizmann process is also key in the aerobic fermentation of sugars to poly(3-hydroxybutyric acid) or PHB (-0[-CH(CH3)-CH2-COO - [70]. This natural and biodegradable polymer is produced inside microorganisms, e.g., Ralstonia eutropha. A complex processing is required to extract and purify the polymer granules from the microorganism. 

Weizmann discovered a process to produce butyl alcohol and acetone from the bacterium Clostridium acetobutylicum in 1914. With England s urgent demand for acetone, Winston Churchill (1874-1965) enlisted Weizmann to develop the Weizmann process for acetone production on an industrial scale. Large industrial plants were established in Canada, India, and the United States to provide the allies with acetone for munitions. Weizmann, who is considered the father of industrial fermentation, obtained significant status from his war contributions and used this to further his political mission of establishing a Jewish homeland. Weizmann was a leader of the Zionist movement and campaigned aggressively until the nation of Israel was established in 1948. He was the first president of Israel. 

The butanols and their methyl and ethyl ethers have several advantages as oxygenates over methanol and ethanol in gasoline blends. Their energy contents are closer to those of gasoline the compatibility and miscibility problems with petroleum fuels are nil excessive vapor pressure and volatility problems do not occur and they are water tolerant and can be transported in gasoline blends by pipeline without danger of phase separation due to moisture absorption. Fermentation processes (Weizmann process) have been developed for simultaneous production of 1-butanol, 2-propanol, acetone, and ethanol from... 

The manufacture of acetone by the Weizmann process attained the greatest success at the factory of British Acetones, Toronto, Ttd., in Canada, where an output of nearly 200 long tons a month was reached. 

It seems, therefore, that the future of the Weizmann process lies abroad, rather than at home, although from tine pure research poini of view much might be attained im tlie laboratories in this country. 

One of the most fascinating stories of the coatings industry involves the production of acetone, butanol, and ethanol by the Weizmann process (11. 12). Because the main objective was to produce acetone for explosives, the butanol piled up until it was found that butyl acetate was an excellent solvent for the new nitrocellulose lacquers. Commercial Solvents Corporation (of Maryland) was formed in 1919 to take over the fermentation plants operating at Terre Haute to make butanol and derivatives. The availability of butyl alcohol and the acetate was of major aid in the success of nitrocellulose lacquers in new automobile paints that permitted a reduction in the time required for painting automobiles from 23 days in 1920 to a matter of about 12 h in 1940 (13). 

The Weizmann process for producing acetone is characterized by the formation of twice the amount of butanol as acetone. Toward the end of the 1910s there was limited need for butanol and Northrup developed P. macerans, at that time called Bacillus acetoethylicum, as an acetone/ethanol producer [12, 13]. The Northrop process was never scaled up to production scale, presumably because -butanol became a valuable product in the lacquer business. 

Clostridium beijerinckii (one of the molasses-fermenting butanol-producing clostridia) is less well known than C. acetobutylicum because many strains of this species were previously given different species names. Clostridium beijerinckii replaced C. acetobutylicum for commercial solvent production after the corn-based Weizmann process was phased out in the late 1930s (Johnson and Chen 1995 Jones et al. 2000). Many extant strains of C. beijerinckii have been definitively identified by DNA-DNA reassociation or a combination of traits and are available from culture collections (Cummins and Johnson 1971 Johnson et al. 1997 Keis et al. 2001a). 

The Weizmann process is based on the fermentation of corn by C. acetobutylicum. The kernel is ground into a coarse meal (Prescott and Dunn 1949) or a fine powder (Beesch 1953 McCutchan and Hickey 1954) and mixed with water and stillage (distillation slop), and the cooked com mash does not require any other nutrients to be added for the fermentation. When it is economical, the germ of com was removed for oil extraction, but the oil-cake meal may be returned to the mash to increase the feed value of the recovered solids at the end of the fermentation. Besides C. acetobutylicum, an unusual variant of Clostridium saccharo-butyl-acetonicum-liquefaciens (known as Code C-12) was also used for the corn-based fermentation, but it required the addition of ammonia to the com mash because of its poor proteolytic power (Walton and Martin 1979). 

Corn and molasses (sugarcane) were the principal raw materials for industrial solvent fermentation. Corn was primarily used during the era of the Weizmann process, which was based on C. acetobutylicum, whereas molasses was used when other bacteria replaced C. acetobutylicum in the industrial fermentation (see the section O Industrial Solvent Fermentation in this chapter). Besides corn and molasses, other starchy substrates were also used in industrial solvent fermentation outside North America. For example, the raw materials for solvent production hy Clostridium toanum Baba in Taiwan (Formosa) between 1947 and 1957 included sweet potato, casava, and wheat starch (a by-product of gluten production Yeh 1955 Anonymous 1956 1958). In addition, a diverse range of raw materials has been tested as alternative substrates for solvent production (McCutchan and Hickey 1954 Prescott and Duim 1959a Jones and Woods 1986 Diirre and Bahl 1996). 

Squibb A process for making acetone by passing acetic acid vapors through an iron tube at 500°C-600°C packed with pumice and precipitated barium carbonate. Invented by E.R. Squibb in 1895 and commercialized in the early twentieth century until supplanted by the Weizmann process. Other ketones have since been made by a similar process. 

ABE fermentation Another name for the Weizmann process used for the production of acetone, butanol, and ethanol using the acid-resistant bacterium Clostridium acetobutylicum. 

Weizmann process A fermentation process used to produce acetone, butanol, and ethanol using the acid-resistant bacterium Clostridium acetobutylicum. The bacteria derived from soil and cereals is able to convert whey, sugar, and starch. The process was developed by Russian-born chemist Chaim Weizmann (1874-1952) and was used in the UK in the First World War for the production of acetone, which was used in the production of cordite. He became a UK citizen in 1910 and then the first president of Israel in 1949. The process is also known as the ABE fermentation. 

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