Fermentation industry acetic acid

Acetic Acid. Methanol carbonylation has become the process of choice for production of this staple of the organic chemical industry, which is used in the manufacture of acetate fibers, acetic anhydride [108-24-7] and terephthaUc acid, and for fermentation (see Acetic acid and derivatives). 

Acetic acid is a weak carboxylic acid with a pungent odor that exists as a liquid at room temperature. It was probably the first acid to be produced in large quantities. The name acetic comes from acetum, which is the Latin word for sour and relates to the fact that acetic acid is responsible for the bitter taste of fermented juices. Acetic acid is produced naturally and synthetically in large quantities for industrial purposes. It forms when ubiquitous bacteria of the genera Acetobacter and Clostridium convert alcohols and sugars to acetic acid. Acetobacter, especially Acetobacter aceti, are more efficient acetic acid bacteria and produce much higher concentrations of acetic acid compared to Clostridium. 

FIG. 19 Schematic flow diagram for the production and purification of fermentation-derived acetic acid, as modified from Office of Industrial Technologies (2003). Unit operation identification items AF, anaerobic fermentation DI, distillation ED, electrodialysis EV, evaporation MF, microfiltration PV, pervaporation-assisted thermal cracking. 

Office of Industrial Technologies. 2003. Production and separation of fermentation-derived acetic acid. In Energy Efficiency and Renewable Energy, US Department of Energy, Washington, DC, (online publication, March, 2003, http //www.oit.doe.gov/chemicals/factsheets/acetic acid. pdf). 

Acetic acid is used in the manufacture of a wide variety of products including adhesives, polyester fibres, plastics, paints, resins and solvents. About 40% of the acetic acid made industrially is used in the manufacture of vinyl acetate monomer for the plastics industry other large uses are to make cellulose acetate, a variety of acetate esters that are used as solvents, as well as monochloracetic acid, a pesticide. Acetic acid is also used as a solvent for the oxidation of p-xylene to terephthalic acid, a precursor to the important polyester, polyethylene terephthalate (PET). A minor, but important use is as non-brewed condiment, a vinegar substitute widely used in British fish and chip shops this is made using food-grade industrial acetic acid and is less expensive than fermentation vinegar. 

Until World War 1 acetone was manufactured commercially by the dry distillation of calcium acetate from lime and pyroligneous acid (wood distillate) (9). During the war processes for acetic acid from acetylene and by fermentation supplanted the pyroligneous acid (10). In turn these methods were displaced by the process developed for the bacterial fermentation of carbohydrates (cornstarch and molasses) to acetone and alcohols (11). At one time Pubhcker Industries, Commercial Solvents, and National Distillers had combined biofermentation capacity of 22,700 metric tons of acetone per year. Biofermentation became noncompetitive around 1960 because of the economics of scale of the isopropyl alcohol dehydrogenation and cumene hydroperoxide processes. 

Wood chips can also be utilized as such to produce bioethanol. The cellulose and hemicellulose material is hydrolyzed in the presence of acids (H2SO4, HCl, or HCOOH) or enzymes to yield glucose and other monosaccharides [16]. Lignin is separated by filtration as a solid residue and the monosaccharides are fermented to ethanol, which, in turn, is separated from water and catalyst by distillation. Ethanol can be used not only as energy source but also as a platform component to make various chemicals, such as ethene and polyethene. Today green acetaldehyde and acetic acid from wood-derived bioethanol is manufactured by SEKAB Ab, at the Ornskoldsvik Biorefinery of the Future industrial park. 

Acetic acid has been produced in relatively large quantities for more than 100 years. The changes in the methods used for its production over this period reflect some of the underlying general trends in the chemical industry. It was originally produced via fermentation, as were many other organic chemicals in the early days of the chemical industry. The first major synthetic process for acetic acid was based on the hydrolysis of acetylene to acetaldehyde catalyzed by mercuric ion. This process was the dominant method of production for more than 40 years, until 1955— 1960, when two new processes were developed which have dominated the acetic acid markets in the past 20 years. Celanese in the United States and British Petroleum in Europe introduced short-chain paraffin oxida-... 

The destructive distillation of wood to produce methanol results in some by-product acetic acid, and that was the most popular but now defunct commercial source. Fermentation, the oldest, indeed the ancient method, is still used to produce vinegar for the food industry. Vinegar is a 3—5% solution of acetic acid in water. 

Acetic acid is an important intermediate organic tonnage chemical that may be produced by the petroleum industry and fermentation. The latter process requires the recovery of acetic acid from water solutions, and several techniques have been applied to this separation, including solvent extraction, azeotropic distillation, and extractive distillation. A comparison of economics between azeotropic distillation and solvent extraction combined with azeotropic distillation (Table 10.3) shows that the introduction of... 

Lactose is readily fermented by lactic acid bacteria, especially Lactococcus spp. and Lactobacillus spp., to lactic acid, and by some species of yeast, e.g. Kluyveromyces spp., to ethanol (Figure 2.27). Lactic acid may be used as a food acidulant, as a component in the manufacture of plastics, or converted to ammonium lactate as a source of nitrogen for animal nutrition. It can be converted to propionic acid, which has many food applications, by Propionibacterium spp. Potable ethanol is being produced commercially from lactose in whey or UF permeate. The ethanol may also be used for industrial purposes or as a fuel but is probably not cost-competitive with ethanol produced by fermentation of sucrose or chemically. The ethanol may also be oxidized to acetic acid. The mother liquor remaining from the production of lactic acid or ethanol may be subjected to anaerobic digestion with the production of methane (CH4) for use as a fuel several such plants are in commercial use. 

Amyl Acetate or Amylacetic EsteKcommonly known as Banana Oil),C H. COOCH, mw 130.18- Several isomers are known of which n-amyl acetate and isoamyl acetate are the most important. They can be prepd by heating amyl alcohols with acetic acid in the presence of some sulfuric acid. Industrial methods of prepn are given in Ref 9,pp 102—3- Commercial products are usually mixts of n- and iso-amyl acetates. When amyl acetate is prepd from "fusel oil (a byproduct obtained in the manuf of ethyl ale by fermentation), the chief component is isoamyl acetate... 

Fermentation of lactic acid to yield propionic acid, carbon dioxide, acetic acid, and succinic acid is important for proper eye formation and flavor development in Emmental, Gruyere, and Swiss-type cheese varieties. This fermentation is associated with Propionibacterium spp. subspecies of Propionibacterium freudenreichii are of greatest significance. These organisms can also be used for industrial production of vitamin Bi2 and propionic acid. 

The anhyd salt decomp when heated at moderate temp. It is sol in w ale. Can be prepd by neutralizing the pyroligneous liquors from hardwood distn with Ca carbonate followed by evapn, drying and purifica-t ior., Until about 1932 it was the only important source for prepn of acetone and acetic acid but the development of the Weiz-mann fermentation process (yielding acetone and synthetic acetic acid), as well as direct acetic acid processes have relegated the salt to a place of minor industrial importance... 

Many industrial organic acids can be produced by fermentation, such as acetic, citric, and lactic acids. Succinic acid is a dicarboxylic acid of potential industrial interest as a platform chemical (1-3). Separation and purification of succinic acid by adsorption was tested to replace current precipitation methods and their associated waste disposal problems. Succinic acid is a valuable intermediate value chemical with a moderate market. For succinic acid to have an economic and energy impact, it will need to become a commodity chemical intermediate with a much lower price. This target price hasbeen estimated to be between 0.22 and 0.30 / lb ( 0.48- 0.66/kg) and is potentially achievable with advanced technology (1). At this price, succinic acid can be catalytically upgraded into other higher valued chemicals suchastetrahydrofuran, 1,4-butanediol, y-butyrolactone, 2-pyrrolidinone, and N-methylpyrrolidinone. 

Species of Clostridium have been used on a very large scale for the production of industrial solvents such as acetone and butanol. Many clostridia ferment sugars with the formation of carbon dioxide, hydrogen and butyric acid. Some of them convert butyric acid to butanol and the acetic acid to ethanol and acetone. The acetone-butanol process by Clostridium acetobutylicum expanded after its introduction just before World War I. Although the industry has now been almost totally replaced by the synthetic production from oil, it may again be of interest for the production of renewable monomers. 

A considerable wood hydrolysis industry with rather old traditions is located in the Soviet Union. The main fermentation product based on hexoses in wood hydrolyzates is ethyl alcohol, but pentoses and aliphatic acids can also be utilized in the production of proteins (see Section 10.2.3). A variety of chemicals, including ethylene, ethylene oxide, acetaldehyde, and acetic acid, can be produced from ethyl alcohol. One interesting future application of ethyl alcohol concerns its use as a motor fuel mixed with gasoline (gasohol). 

There are many organic acids that can be produced by microbial or biochemical means. However, at present, only acetic acid (as vinegar), citric acid, itaconic acid, gluconic acid, 2-keto-gulonic acid, and lactic acid are produced industrially by fermentation. Other organic acids, such as fumaric, gallic, malic, and tartaric acids, once produced by fermentation or enzyme processes, are now produced commercially, predominantly by the more economic means of chemical synthesis. 

Mankind has produced acetic acid for many thousand years but the traditional and green fermentation methods cannot provide the large amounts of acetic acid that are required by today s society. As early as 1960 a 100% atom efficient cobalt-catalyzed industrial synthesis of acetic acid was introduced by BASF, shortly afterwards followed by the Monsanto rhodium-catalyzed low-pressure acetic acid process (Scheme 5.36) the name explains one of the advantages of the rhodium-catalyzed process over the cobalt-catalyzed one [61, 67]. These processes are rather similar and consist of two catalytic cycles. An activation of methanol as methyl iodide, which is catalytic, since the HI is recaptured by hydrolysis of acetyl iodide to the final product after its release from the transition metal catalyst, starts the process. The transition metal catalyst reacts with methyl iodide in an oxidative addition, then catalyzes the carbonylation via a migration of the methyl group, the "insertion reaction". Subsequent reductive elimination releases the acetyl iodide. While both processes are, on paper, 100%... 

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