Industrial solvents acetic acid

Table 9.2 summarizes the uses of acetic acid. Vinyl acetate is another top 50 chemical. Acetic anhydride is used to make cellulose acetate and at times has been in the top 50 chemicals itself. Cellulose acetate is a polymer used mainly as a fiber in clothing and cigarette filters. Ethyl acetate is a common organic solvent. Acetic acid is used as a solvent in the manufacture of terephthalic acid (TA) and dimethyl terephthalate (DMT), which are monomers for the synthesis of poly(ethylene terephthalate), the polyester of the textile industry. A minor household use of acetic acid is as a 3-5% aqueous solution, which is called vinegar. 

We will begin with the carbonylation of Mel which in situ is generated from MeOH for acetic acid production because of its industrial importance. Acetic acid is an important chemical commodity with a wide range of appUcations in organic chemistry. In organic synthesis, acetic acid is mainly used as a raw material for vinyl acetate monomers and acetic anhydride synthesis, as well as a solvent for producing terephthalic acid from xylene via the oxidation process. In 1998 the world s capacity of acetic acid production was approximately 7.8 milUon tons, of which more than 50 % were produced by BP-Amoco and Celanese. 

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. 

The Phenox process (254) removes phenol (qv) from the efduent from catalytic cracking in the petroleum industry. Extraction of phenols from ammoniacal coke-oven Hquor may show a small profit. Acetic acid can be recovered by extraction from dilute waste streams (255). Oils are recovered by extraction from oily wastewater from petroleum and petrochemical operations. Solvent extraction is employed commercially for the removal of valuable... 

Solvent Extraction Reagents. Solvent extraction is a solution purification process that is used extensively in the metallurgical and chemical industries. Both inorganic (34,35) and organic (36) solutes are recovered. The large commercial uses of phosphine derivatives in this area involve the separation of cobalt [7440-48-4] from nickel [7440-02-0] and the recovery of acetic acid [61-19-7] and uranium [7440-61-1]. 

In a similar appHcation, Cape Industries has announced its intention to commission a solvent extraction plant to recover acetic acid from an effluent generated at its dimethyl terephthalate [120-61-6] faciHty (Wilmington, North Carolina) (44,45). The plant was commissioned in Eebmary 1995. In this case, the solvent will be CYANEX 923 extractant [100786-00-3], CYANEX 923 is also a phosphine oxide, but unlike TOPO is a Hquid and can be used without a diluent (46,47). This has the benefit of reducing plant size, capital, and operating costs. 

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). 

For lab prepns, and occasionally in industrial use, more expensive nitrating agents may be employed, as for example solns of nitric acid in inert organic solvents (chlf, carbon tetrachloride, eth, nitromethane, etc), or a soln of nitric acid in phosphoric or acetic acids or in acetic anhydride, trifluoroacetic anhydride or trifluoro-me thane sulfonic acid (Ref 94)... 

Methanol is used in industry as a raw material for formaldehyde (40-50%), as a solvent, and for producing, for example, acetic acid by hydroformylation. The latter is used, for example, to make precursors for polymers. 

Oxygen, in the air, is probably the cheapest, most readily available oxidant and so it is not suprising that industrial processes using this reagent for the oxidation of sulphoxides has been patented. These procedures involve the use of transition metal ion catalysts " in solvents containing acetic acid , acetone and carboxylic acids . 

Uses. About 35-40% of the methanol made is converted to formaldehyde. That s not because the embalming business is so good. Formaldehyde is a feedstock for amino and phenolic resins, which are used as adhesives in plywood, and in the automotive and appliance industry to make parts (all the agitators in washing machines used to be made out of phenolic resins). It is used as feedstock for hexamethylene tetramine, used in electronic plastics for pentaerythritol, used for making enamel coatings and for floor polish and inks for butanediol, a chemical intermediate and for acetic acid, which is widely used itself as a feedstock and solvent and warrants its own treatrnent later on. In the textile business, formaldehyde is used to make fire retardants, mildew resistant linens, and permanent press clothing. 

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... 

As in all large-scale industrial processes, the formation of the cellulose esters involves recovery of materials. Acetic anhydride is generally employed. After reaction, acetic acid and solvent are recovered. The recovered acetic acid is employed in the production of additional acetic anhydride. The recovered solvent is also reintroduced after treatment. 

The selective oxidation of saturated hydrocarbons is a reaction of high industrial importance. Besides a variety of other oxidants, hydrogen peroxide as a very clean oxidant has also been used for these purposes . As an example, in 1989 Moiseev and coworkers reported on the vanadium(V)-catalyzed oxidation of cyclohexane with hydrogen peroxide (Scheme 146) . When the reaction was carried out in acetic acid cyclohexanol and cyclohexanone were formed, bnt conversions were very poor and did not exceed 13%. Employing CF3COOH as solvent, complete conversions could be obtained within 5 min-ntes. Here, cyclohexyl trifluoroacetate was the main product (85% of the products formed) resulting from the reaction of cyclohexanol (the primary product of the oxidation) with CF3COOH. 

Production of phenol and acetone is based on liquid-phase oxidation of isopropylbenzene. Synthetic fatty acids and fatty alcohols for producing surfactants, terephthalic, adipic, and acetic acids used in producing synthetic and artificial fibers, a variety of solvents for the petroleum and coatings industries—these and other important products are obtained by liquid-phase oxidation of organic compounds. Oxidation processes comprise many parallel and sequential macroscopic and unit (or very simple) stages. The active centers in oxidative chain reactions are various free radicals, differing in structure and in reactivity, so that the nomenclature of these labile particles is constantly changing as oxidation processes are clarified by the appearance in the reaction zone of products which are also involved in the complex mechanism of these chemical conversions. 

Of course, a number of solvents in common use in the chemical industry, such as ethanol, acetic acid, and ethyl acetate, can be derived from either bio or oil raw materials. The debate rages over the hfe cycle impact of bio versus fossil fuel... 

Ethanol (industrial solvent Acetaldehyde (used in used in preparation of ethyl preparation of acetic acid) acetate unleaded gasoline additive)... 

Benzoic acid is an important chemical intermediate which can also be used as a phenol precursor by decarbonylation in the presence of copper catalysts (Lummus process). It is produced industrially by oxidation of toluene by air in the presence of cobalt catalysts (Dow and Amoco processes equation 240). The reaction can be carried out without solvent, or in an acetic acid solvent. The oxidation of toluene without solvent uses a cobalt octoate catalyst and operates at higher temperature (180-200 CC). Yields of benzoic acid are about 80% for ca. 50% toluene conversion.361 In an acetic acid solution and in the presence of cobalt acetate, the reaction occurs at lower temperature conditions (110-120 °C) and gives higher yields in benzoic acid (90%).83,84... 

This is one of the most important industrial oxidation processes. Terephthalic acid (TPA) is mostly used for the manufacture of polyester fibers, films and plastics, and its world production capacity reaches 8 Mt/year. Two major processes have been developed. The Amoco-Mid Century process produces terephthalic acid by the one-step oxidation of p-xylene in acetic acid, whereas the Dynamit Nobel process yields dimethyl terephthalate in several steps and in the absence of solvent.83,84,86... 

The industrial solvent ethyl acetate is produced by reaction of acetic acid with ethanol ... 

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