Acetate production from ethanol

The balanced equation for production of acetic acid from ethanol is... 

The production of vinegar from ethanol, gluconic acid from glucose and many steroids are examples of currently used industrial-scale bioconversions. The production of acetic acid from ethanol is characteristic of Acetobacter or Gluconobacter species. One gram of ethanol theoretically produces 1.304 g acetic acid 34). Aspergillus,... 

Nitration of acetanilide. Add 25 g (0.185 mol) of finely powdered, dry acetanilide to 25 ml of glacial acetic acid contained in a 500-ml beaker introduce into the well-stirred mixture 92 g (50 ml) of concentrated sulphuric acid. The mixture becomes warm and a clear solution results. Surround the beaker with a freezing mixture of ice and salt, and stir the solution mechanically. Support a separatory funnel, containing a cold mixture of 15.5 g (11ml) of concentrated nitric acid and 12.5 g (7 ml) of concentrated sulphuric acid, over the beaker. When the temperature of the solution falls to 0-2 °C, run in the acid mixture gradually while the temperature is maintained below 10 °C. After all the mixed acid has been added, remove the beaker from the freezing mixture, and allow it to stand at room temperature for 1 hour. Pour the reaction mixture on to 250 g of crushed ice (or into 500 ml of cold water), whereby the crude nitroacetanilide is at once precipitated. Allow to stand for 15 minutes, filter with suction on a Buchner funnel, wash it thoroughly with cold water until free from acids (test the wash water) and drain well (1). Recrystallise the pale yellow product from ethanol or industrial spirit, filter at the pump, wash with a little cold alcohol and dry in the air upon filter paper (2). (The yellow o-nitroacetanilide remains in the filtrate.) The yield of p-nitroacetanilide, a colourless crystalline solid of m.p. 214 °C, is... 

Corza, G., Revah, S. and Christen, P. Effect of Oxygen on the Ethyl Acetate Production from Continous Ethanol Stream by Candida utihs in Submerged Cultures, fn Food Flavors Generation, Analysis and Process Influence (Charalambous, G., ed.). Amsterdam, Elsevier, pp. 1141-1154 (1995)... 

This calculation is based on that 2 molecules of hydrogen are produced from 1 molecule of glucose. Amount of gluoose consumed in PFL-LDH is estimated by the sum of the amount lactate production, pyruvate production,acetate production, and ethanol production 204 mmo) in MC4100 and 160 mmol in MC13-4. 

Whole-cell based biocatalysis utilizes an entire microorganism for the production of the desired product. One of the oldest examples for industrial applications of whole-cell biocatalysis is the production of acetic acid from ethanol with an immobilized Acetobacter strain, which was developed nearly 200 yr ago. The key advantage of whole-cell biocatalysis is the ability to use cheap and abundant raw materials and catalyze multistep reactions. Recent advances in metabolic engineering have brought a renaissance to whole-cell biocatalysis. In the following sections, two novel industrial processes that utilize whole-cell biocatalysis are discussed with emphasis on the important role played by metabolic engineering. 

The acetic acid bacteria produce acetic acid from ethanol hy two enzyme-catalyzed reactions of memhrane-hound alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). In addition, some acetic acid bacteria can oxidize various sugars and sugar alcohols. These reactions are all incomplete oxidations because the oxidation products are usually accumulated in large amounts in the bacterial beers. Both ADH and ALDH have pyrroloquinohne quinone (PQQ) bound as a prosthetic group and are linked to the respiratory chain in the cytoplasmic membrane (O Fig. 1.3). A second set of NAD(-P) -dependent ADHs and ALDHs is found in the cytoplasm of acetic add bacteria. These latter two enzymes have much lower specific activities than those of the PQQ-enzymes and are not involved in acetic add production (seeO Fig. 1.3). 

Younesi H., Najafpour G, Mohamed AR. 2005. Ethanol and acetate production from synthesis gas via fermentation processes using anaerobic bacterium. Biochemical Engineering 27 110-119. 

Fig. 6.4 compares the anode and cathode polarization between AEM and CEM. The cathode potential was increased about 200 mV with AEM compared with CEM, whereas the anode potential decreased to 80-300 mV depending on the current density. The advantage of AEM-type DEFCs is based on reduction of both anode and cathode over voltages [16]. Quantitative analyses of the product species during the operation of DEFCs were carried out to determine the stoichiometry of DEFCs. The formation of acetaldehyde or acetic acid as an oxidation product from ethanol was expected during the operation of AEM-type DEFCs, as described by Eqs. (6.4)... 

Dissolve 10 g. of chloro- 2,4-dinitrobenzenet in 50 ml. of dioxan in a 250 ml. conical flask. Dilute 8 ml. of hydrazine hydrate with an equal volume of water and add this slowly with shaking to the dioxan solution, keeping the temperature between zo " and 25°. Heat under reflux for 10 minutes to complete the reaction and then add 5 ml. of ethanol and heat again for 5 minutes. Cool and filter oflF the orange 2,4-dinitrophenylhydra-zine. Recrystallise the dry product from ethyl acetate m.p. 200° (decomp.). Yield, 7 g. 

Mix 6 2 ml. (6 4 g.) of pure ethyl acetoacetate and 5 ml. of pure phenylhydrazine in an evaporating-basin of about 75 ml. capacity, add 0 5 ml. of acetic acid and then heat the mixture on a briskly boiling water-bath (preferably in a fume-cupboard) for I hour, occasionally stirring the mixture with a short glass rod. Then allow the heavy yellow syrup to cool somewhat, add 30-40 ml. of ether, and stir the mixture vigorously the syrup may now dissolve and the solution shortly afterwards deposit the crystalline pyrazolone, or at lower temperatures the syrup may solidify directly. Note. If the laboratory has been inoculated by previous preparations, the syrup may solidify whilst still on the water-bath in this case the solid product when cold must be chipped out of the basin, and ground in a mortar with the ether.) Now filter the product at the pump, and wash the solid material thoroughly with ether. Recrystallise the product from a small quantity of a mixture of equal volumes of water and ethanol. The methyl-phenyl-pyrazolone is obtained... 

The production of acetic acid from butane is a complex process. Nonetheless, sufficient information on product sequences and rates has been obtained to permit development of a mathematical model of the system. The relationships of the intermediates throw significant light on LPO mechanisms in general (22). Surprisingly, ca 25% of the carbon in the consumed butane is converted to ethanol in the first reaction step. Most of the ethanol is consumed by subsequent reaction. 

A Belgian patent (178) claims improved ethanol selectivity of over 62%, starting with methanol and synthesis gas and using a cobalt catalyst with a hahde promoter and a tertiary phosphine. At 195°C, and initial carbon monoxide pressure of 7.1 MPa (70 atm) and hydrogen pressure of 7.1 MPa, methanol conversions of 30% were indicated, but the selectivity for acetic acid and methyl acetate, usehil by-products from this reaction, was only 7%. Ruthenium and osmium catalysts (179,180) have also been employed for this reaction. The addition of a bicycHc trialkyl phosphine is claimed to increase methanol conversion from 24% to 89% (181). 

Ethanol s use as a chemical iatemiediate (Table 8) suffered considerably from its replacement ia the production of acetaldehyde, butyraldehyde, acetic acid, and ethyUiexanol. The switch from the ethanol route to those products has depressed demand for ethanol by more than 300 x 10 L (80 x 10 gal) siace 1970. This decrease reflects newer technologies for the manufacture of acetaldehyde and acetic acid, which is the largest use for acetaldehyde, by direct routes usiag ethylene, butane (173), and methanol. Oxo processes (qv) such as Union Carbide s Low Pressure Oxo process for the production of butanol and ethyUiexanol have totaUy replaced the processes based on acetaldehyde. For example, U.S. consumption of ethanol for acetaldehyde manufacture declined steadily from 50% ia 1962 to 37% ia 1964 and none ia 1990. Butadiene was made from ethanol on a large scale duriag World War II, but this route is no longer competitive with butadiene derived from petroleum operations. 

Acetaldehyde. Until the early 1970s, the maia use of iadustrial ethanol was for the production of acetaldehyde [75-07-0]. By 1977, the ethanol route to acetaldehyde had largely been phased out ia the United States as ethylene and ethane became the preferred feedstocks for acetaldehyde production (286—304). Acetaldehyde usage itself has also changed two primary derivatives of acetaldehyde, acetic acid, and butanol, are now produced from feedstocks other than acetaldehyde. Acetaldehyde is stiU produced from ethanol ia India. 

After an additional 10 min, a 1 % solution of hydrochloric acid (100 ml) is slowly added to the stirred reaction mixture and the resultant mixture is transferred to a separatory funnel. The ether layer is separated and washed sequentially with water, 5 % sodium bicarbonate solution, water and saturated salt solution. The washed ether solution is dried over anhydrous sodium sulfate, filtered, and evaporated to give an oily residue (0.45 g). Chromatography of the crude product on silica gel (50 g) followed by crystallization of the solid thus obtained (0.18 g) from ethanol gives 3 -hydroxy-B-homo-cholest-5-en-7a-one acetate (67 0.14 g) mp 90-91° [a]o 99° (CHCI3). 

Methoxy-D-Homo-estra-l,3,5(10)-trien-17a-one (96)" (/) Acetic acid (6.4 ml) is added to a stirred solution of estrone methyl ether (93 1.1 g) in ethanol (35 ml) containing potassium cyanide (6 g) at 0°. After being stirred for 1 hr at 0° and 2.5 hr at room temperature, the reactants dissolve and potassium acetate preciptates. Water (65 ml) is added to the reaction mixture and the precipitated solid is collected by filtration. The crude product is dissolved in ethyl acetate and the ethyl acetate solution is washed with water, dried over anhydrous magnesium sulfate and evaporated to dryness under reduced pressure. Recrystallization of a portion of the crude product from cyclohexane-acetone gives 3-methoxy-17a-cyano-estra-l, 3,5(10)-trien-17j5-ol (94a) as needles mp 158.5°. 

A solution of 10 g (0.023 mole) of cholesteryl acetate (mp 112-114°) in ether (50 ml) is mixed with a solution containing 8.4 g (0.046 mole) of monoperphthalic acid (Chapter 17, Section II) in 250 ml of ether. The solution is maintained at reflux for 6 hours, following which the solvent is removed by distillation (steam bath). The residue is dried under vacuum and digested with 250 ml of dry chloroform. Filtration of the mixture gives 6.7 g of phthalic acid (87% recovery). The solvent is evaporated from the filtrate under reduced pressure and the residue is crystallized from 30 ml of methanol, giving 6.0 g (58% yield) of -cholesteryl oxide acetate. Recrystallization affords the pure product, mp 111-112°. Concentration of the filtrate yields 1.55 g (15% yield) of a-cholesteryl oxide acetate which has a mp of 101-103° after crystallization from ethanol. 

Solid sodium nitrite (0.97 g) was added at room temperature with stirring over a period of one hour to a solution of 2-chloro-9-(2-hydroxyethoxymethyl)adenine (0.5 g) in glacial acetic acid (10 ml). The reaction mixture was stirred for an additional A A hours. The white solid was removed by filtration, washed with cold acetic acid and then well triturated with cold water to remove the sodium acetate present. The solid product was retained. The combined acetic acid filtrate and wash was evaporated at reduced pressure and 40°C bath temperature and the residual oil triturated with cold water. The resulting solid material was combined with the previously isolated solid and the combined solids dried and recrystallized from ethanol to give 2chloro-9-(2-hydroxyethoxymethyl)+iypoxanthine (0.25 g), MP>310°C. Elemental analysis and NMR spectrum were consistent with this structure. 

To a mixture of 3.0 grams of N,N -diacetyl-o-anilamide and 20 ml of acetic acid Is added a previously prepared solution of 1.5 grams of chlorine in 31 cc of acetic acid. The reaction mixture is allowed to stand at room temperature for 3 hours and is then evaporated to dryness on a steam bath under reduced pressure. The resulting solid residue is recrystallized from ethanol, yielding the intermediate N,N -diacetyl-2-sulfamyl-4-chloroaniline. The intermediate compound is fused in an oil bath at 250-260°C for 15 minutes, cooled and the product so obtained is crystallized from 80% ethanol yielding 3-methyl-7-chloro-1,2,4-benzo-thiadiazine-1,1-dioxide, MP 330°C. 

A mixture of 2.9 grams of 5-chloro-2,4-disulfamvl-aniline in 20 ml of anhydrous diethylene-glycol dimethylether, 0.44 gram of propionaldehyde and 0.5 ml of a solution of hydrogen chloride in ethyl acetate (109.5 grams hydrogen chloride per 1,000 ml) Is heated to 80° to 90°C and maintained at that temperature for 1 hour. The reaction mixture is concentrated under reduced pressure on addition of water, the product separates and is then recrystal-lized from ethanol or aqueous ethanol to yield the desired 6-chloro-3-ethvl-7-sulfamyl-3,4-dihydro-1,2,4-benzothiadiazine-1,1-dioxide, MP 269° to 270°C. 

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