Ethanol from fermentation

Carbon dioxide also is produced along with ethanol from fermentation of carbohydrates by yeast ... 

Ethanol from fermentation is relatively expensive because of the great financial and environmental costs of growing food biomass, a process that requires vast amounts of water and fertilizer. Ethanol derived from petroleum is actually less expensive. (But only because crude oil prices are kept artificially low. If taxpayer subsidies, exemptions from paying for the environmental damage from mining and drilling, and the cost of military protection are factored in, the price of crude oil quadruples.)... 

Anhydrous ethanol from fermentation broth 176 Azeotrope problem ... 

Extraction of Ethanol from Fermentation Broth Using Supercritical CO2... 

Thibault et al [14] investigated experimentally the production of ethanol by fermentation under CO2 pressure, but they were not successful due to the negative effect of pressure on the microorganisms used. L ltalien et al [15] attempted to improve the ethanol fermentation under hyperbaric conditions with limited success. The separation of ethanol from fermentation broth, however, was not investigated thoroughly. 

Ethanol From fermentation of plant-derived starch Reduced attraction of... 

In one process, the inventor has reported that sugars from oilseed meals are readily fermented to form ethanol (80). With soybeans, the concentration of fermentable sugars can constitute 12% of the meal weight. These sugars could readily be fermented to produce enough ethanol for esterification of oil from the seed. However, it is improbable that seeds with higher oil contents would produce sufficient ethanol from fermentation to esterify the oils present. 

See alcohol, denatured alcohol, industrial biomass. Note Ethanol from fermentation of biomass and hydrolysis of cellulose is a significant alternate energy source, especially as an automotive fuel. Its use in gasoline will continue to increase. 

TABLE 16.13 Trends in the U.S. Supply of Industrial Ethanol from Fermentation Versus Synthetic Sources"... 

Ethylene for polymerization to the most widely used polymer can be made by the dehydration of ethanol from fermentation (12.1).6 The ethanol used need not be anhydrous. Dehydration of 20% aqueous ethanol over HZSM-5 zeolite gave 76-83% ethylene, 2% ethane, 6.6% propylene, 2% propane, 4% butenes, and 3% /3-butane.7 Presumably, the paraffins could be dehydrogenated catalyti-cally after separation from the olefins.8 Ethylene can be dimerized to 1-butene with a nickel catalyst.9 It can be trimerized to 1-hexene with a chromium catalyst with 95% selectivity at 70% conversion.10 Ethylene is often copolymerized with 1-hexene to produce linear low-density polyethylene. Brookhart and co-workers have developed iron, cobalt, nickel, and palladium dimine catalysts that produce similar branched polyethylene from ethylene alone.11 Mixed higher olefins can be made by reaction of ethylene with triethylaluminum or by the Shell higher olefins process, which employs a nickel phosphine catalyst. 

Ethanol permselective membrane system has been used for the extraction of ethanol from fermentation broth. However, both membrane distillation and polymeric silicon rubber membranes showed low separation factors of ethanol and were invalid in this case. M. Nomura et al. [26] investigated the continuous extraction of ethanol from ethanol fermentation broth through a silicalite-1 membrane. From 4.73wt.% ethanol concentration of broth, the permeate ethanol concentration was 81.0wt.%. In our group, we have also investigated the potentiality of silicalite-1 membrane for alcohol extraction from aqueous solution [27]. 

Pangarkar VG. 2002. Separation of ethanol by pervaporation (In-situ recovery of ethanol from fermentation broth). Technical proposal for funding by Department of Biotechnology, Government of India, New Delhi, India. 

Wasewar K L and Pangarkar V G (2006), Intensification of recovery of ethanol from fermentation broth nsing pervaporation economical evalnation , Chem Biochem Eng <2,20,135-145. 

Bui, S., X. Veryldos, and R. Mutharasan. 1985. In-situ Removal of Ethanol from Fermentation Broths. I. Selective Adsorption Characteristics, Industrial and Engineering Chemistry Process Design and Development, vol. 24, no. 4, pp. 1209-1213. 

Ethanol isolation proceeds via distUlative processes. Owing to the formation of an ethanol/water azeotrope (95.5 mass% ethanol at 1 bar), the production of water-free ethanol requires the application of extractive distillation (typical entrainer benzene or cyclohexane, see Section 3.3.2.3). The isolation of water-free ethanol from fermentation is a relatively energy intense step. Even with a clever combination of several distillation columns working at different pressures, the energy input to produce 1 kg of bioethanol by fermentation is about 10 MJ (Baerns et al, 2006). In a few countries, where the production of bioethanol is particularly cheap (e.g., Brazil), there have also been attempts to convert bioethanol into chemicals in commercial scenarios. The production of ethylene from bioethanol is a potential option in this context. 

Endless screw type stills are used for continuous distillation especially in Russia for the last 40 5 years. In this system, while finely powdered plant material slowly moves downward, countercurrent steam liberates and carries away the oil, which is condensed and collected in the usual way. Continuous distillation is applied by the industry to produce cedarwood, fennel, pine, juniper oils, and ethanol from fermented grapes. 

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