Eastman Chemical acetic acid

Similar intermediates are possibly involved in the Halcon/Eastman route to acetic anhydride from methyl acetate ", and BP Chemicals acetic acid/acetic anhydride co-production process, both now commercialized. However, all these cyclic mechanisms may be incomplete, as individual steps may themselves be complex or catalysed by other species present, and the author has omitted many (minor) side-reactions. 

The Eastman Chemicals from Coal faciUty is a series of nine complex interrelated plants. These plants include air separation, slurry preparation, gasification, acid gas removal, sulfur recovery, CO /H2 separation, methanol, methyl acetate, and acetic anhydride. A block flow diagram of the process is shown in Eigure 3. The faciUty covers an area of 2.2 x 10 (55 acres) at Eastman s main plant site in Kingsport, Teimessee. The air separation plant is... 

The chemical complex includes the methanol plant, methyl acetate plant, and acetic anhydride plant. The methanol plant uses the Lurgi process for hydrogenation of CO over a copper-based catalyst. The plant is capable of producing 165,000 t/yr of methanol. The methyl acetate plant converts this methanol, purchased methanol, and recovered acetic acid from other Eastman processes into approximately 440,000 t/yr of methyl acetate. 

Acetaldehyde can be used as an oxidation-promoter in place of bromine. The absence of bromine means that titanium metallurgy is not required. Eastman Chemical Co. has used such a process, with cobalt as the only catalyst metal. In that process, acetaldehyde is converted to acetic acid at the rate of 0.55—1.1 kg/kg of terephthahc acid produced. The acetic acid is recycled as the solvent and can be isolated as a by-product. Reaction temperatures can be low, 120—140°C, and residence times tend to be high, with values of two hours or more (55). Recovery of dry terephthahc acid follows steps similar to those in the Amoco process. Eastman has abandoned this process in favor of a bromine promoter (56). Another oxidation promoter which has been used is paraldehyde (57), employed by Toray Industries. This leads to the coproduction of acetic acid. 2-Butanone has been used by Mobil Chemical Co. (58). 

Eastman Chemical Co. uses only cobalt and bromine, and lower temperature oxidations are held at 175—230°C (83). Solution of 4-formylbenzoic acid is obtained by using hydroclones to replace the mother hquor from the first oxidation with fresh acetic acid. A residence time of up to 2 h is used in order to allow for sufficient digestion to take place and to reduce the 4-formylbenzoic acid content to 40—270 ppm (83). Recovery of dry terephthahc acid is as described above. 

Eastman Chemical Company has operated a coal-to-methanol plant in Kingsport, Tennessee, since 1983. Two Texaco gasifiers (one is a backup) process 34 Mg/h (37 US ton/h) of coal to synthesis gas. The synthesis gas is converted to methanol by use of ICl methanol technology. Methanol is an intermediate for producing methyl acetate and acetic acid. The plant produces about 225 Gg/a (250,000 US ton/a) of acetic anhydride. As part of the DOE Clean Coal Technology Program, Air Products and Cnemicals, Inc., and Eastman Chemic Company are constructing a 9.8-Mg/h (260-US ton/d) slurry-phase reactor for the conversion of synthesis gas to methanol and dimethyl... 

The most successful example of generating chemicals directly from coal is the Tennessee Eastman integrated process for producing acetic anhydride. The commercial plant gasifies approximately 900 tons of coal per day and performs four chemical steps to yield annually 500 million pounds of acetic anhydride, 390 million pounds of methyl acetate, and 365 million pounds of methanol. In addition, 150 million pounds per year of acetic acid may be produced from acetic anhydride. 

Recently, Eastman Chemical Company reported that ionic liquids can be successfully employed in a vapor take-off process for the carbonylation of methanol to acetic acid in the presence of rhodium and methyl iodide (3). While attempting to extend this earlier work to the carbonylation of ethylene to propionic acid, we discovered that, when using ionic liquids as a solvent, acceptable carbonylation rates could be attained in the absence of any added alkyl iodide or hydrogen iodide (4). We subsequently demonstrated that the carbonylation of methanol to acetic acid could also be operated in the absence of methyl iodide when using ionic liquids (5). 

Methanol is an ideal starting material for the synthesis of many chemicals. It is the most important feedstock for the large-scale commercial production of acetic acid and formaldehyde. Additionally, a variety of other chemicals such as methyl esters, methyl halides and methyl ethers can be produced from it. Tenessee-Eastman s recent pioneering commercialization of a coal-based process for acetic anhydride production illustrates the growing importance of methanol as chemical feedstock. 

Hydrocarbons were purchased from Eastman and Aldrich and, where necessary, purified to 99+% purity. Hemimellitene was furnished by M. C. Hoff, Amoco Chemicals Corp. Acetic acid was J. T. Baker ACS reagent grade cobalt acetate and cobalt bromide were Fisher certified grade. 

Systems that have the most potential for reactive distillation are those where the reaction is reversible, heat of reaction is not excessively large, and the products have the correct volatilities in relation to the reactants. Those systems reach chemical equilibrium (i.e., reaction stops) unless the reactants are in large excess or the products are continuously removed. An example system has been reported in the literature by Eastman Chemical (Agreda et al., 1990) for the production of methyl acetate from methanol and acetic acid. The discussion about process operation and the control strategy shown in the paper certainlv adhere to the plantwide control principles we have outlined in this book. 

The following components were used as supplied boron trifluoride etherate, Eastman white label chloroform and mcthylal, Fischer reagent glacial acetic acid, du Pont reagent 1,3-propanedithiol, Aldrich Chemical Co. The submitters have scaled up this preparation by a factor of 5 without difficulty. 

The main difference between the Monsanto acetic acid process and Tennessee Eastman acetic anhydride process is the presence of water in the acetic acid process, which produces HI and acetic acid. In both reactions, a small amount of H2 is added to the CO stream to act as a reducing agent to keep the catalyst in the more active Rh oxidation state. An engineering problem with both processes is the highly corrosive nature of the Hl/iodide mixture, requiring the use of special chemically resistant alloys, pumps, and seals. 

Eastman Chemical Company, together with Halcon, developed a commercial acetic anhydride process to an industrial scale [41b, 47]. This process starts with coal to make a hydrogen-rich synthesis gas, which is purified (Figure 4). A portion of the syn gas is separated to produce methanol from 2 1 H2/CO. Part of the methanol is used to scrub H2S from the coal-gasification step. The remainder of the methanol is combined with acetic acid to make methyl acetate. The methyl acetate is carbonylated to give acetic anhydride. The acetic anhydride is used to produce cellulose acetate in another process, and the resulting acetic acid is recycled to the esterification section. The acetic anhydride step of the pro-... 

On the basis of this development afforded by Eastman and Halcon, in 1983 the Eastman Chemical Company (Kingsport, TN) started the commercial process for the manufacture of acetic anhydride (Figure 5). Methyl acetate, the feedstock for the carbonylation reaction, was produced in a separate esterification step from acetic acid and methanol. The process was designed to produce 225 000 tons of acetic anhydride and 75 000 tons of acetic acid/year. The overall yield of acetic anhydride based on methanol is approximately 96 % [2, 47]. 

Because acetic anhydride is more useful to the chemical industry than acetic acid, there was economic incentive to develop a process that would yield the anhydride directly without first producing the acid as a separate operation. By the early 1980s, Eastman Chemicals, in conjunction with Halcon Chemical Company, developed a procedure that provided acetic anhydride using technology similar to the Monsanto process, and since 1991 a plant run by Eastman has produced anhydride in excess of 500,000 metric tons per year.89 The Eastman-Halcon (E-H) operation amounts formally to inserting CO into the C-0 bond of methyl acetate according to equation 9.36.90... 

There are many examples of the application of CD or RD for esterification.f" Esterification of methanol or ethanol with acetic acid forms methyl acetate or ethyl acetate, respectively. Methyl acetate is important in the manufacture of polyesters and is an important solvent for cellulose while ethyl acetate is used in inks, fragrances, and pharmaceuticals. The manufacture of high-purity methyl acetate is difficult because of the equilibrium limitation and also the formation of azeotropes. The production of methyl acetate by Eastman Chemical Co. was the first commercial application of RD using a homogeneous liquid acid catalyst. Only one RD column and two smaller columns for processing sidestreams are required while in the conventional methyl acetate synthesis, two reactors and eight distillation columns are required. 

NDMA is not produced for commercial use in the United States (HSDB 1988). The public portion of the U.S. EPA TSCA Production File indicates that during 1977, the Ames Laboratories in Milford, CT and Columbia Organics in Columbia, SC both prepared small research quantities of this chemical. Eastman-Kodak in Rochester, NY and Teledyne McCormick Selph, an importer, supplied no NDMA during 1977, although both had the capability to produce/import this compound and had done so in the past (EPA 1977). Small research quantities of this chemical presently are available from Sigma Chemical Co. and Aldrich Chemical Co. NDMA can be prepared by reaction of nitrous acid with dimethylamine or by addition of acetic acid and sodium... 

Acetic anhydride is used in the manufacture of cellulose acetate-based film, cigarette filters, and plastics. Eastman Chemical developed a process that is based on gasification of coal in a Texaco gasifier to make synthesis gas which then is converted to methanol. The methanol is converted to methyl acetate by esterification with acetic acid and then carbonylated. The carbonylation process uses rhodium salt catalysts with ligands and an iodine promoter [30]. 

Over the years a variety of uses have been found for the isobutyraldehyde by Eastman Chemical and others.219 It is converted to isobutyl alcohol, neopentyl glycol, isobutyl acetate, isobutyric acid, isobutylidenediurea, methyli-soamyl ketone, and various hydrogenation and esterification products (1.22). 

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