Adipic acid for nylon

Adipic acid is a very large volume organic chemical. Worldwide production in 1986 reached 1.6 x 10 t (3.5 x 10 lb) (158) and in 1989 was estimated at more than 1.9 x 10 t (Table 7). It is one of the top fifty (159) chemicals produced in the United States in terms of volume, with 1989 production estimated at 745,000 t (160). Growth rate in demand in the United States for the period 1988—1993 is estimated at 2.5% per year based on 1987—1989 (160). Table 7 provides individual capacities for U.S. manufacturers. Western European capacity is essentially equivalent to that in the United States at 800,000 t/yr. Demand is highly cycHc (161), reflecting the automotive and housing markets especially. Prices usually foUow the variabiUty in cmde oil prices. Adipic acid for nylon takes about 60% of U.S. cyclohexane production the remainder goes to caprolactam for nylon-6, export, and miscellaneous uses (162). In 1989 about 88% of U.S. adipic acid production was used in nylon-6,6 (77% fiber and 11% resin), 3% in polyurethanes, 2.5% in plasticizers, 2.7% miscellaneous, and 4.5% exported (160). 

The most important use of cyclohexanone is as a chemical intermediate in nylon manufacture 97% of all cyclohexanone output is used either to make caprolactam for nylon-6, or adipic acid for nylon-6,6. In the caprolactam process cyclohexanone is converted to cyclohexanone oxime (mp,... 

Adipic acid is a very large-volume organic chemical. It is one of the top 50 chemicals produced in the United States in terms of volume. Demand is highly cyclic, reflecting the automotive and housing markets especially. Prices usually follow the variability in crude oil prices. Adipic acid for nylon takes about 60% of U.S. cyclohexane production the remainder goes to caprolactam for nylon-6, export, and miscellaneous uses. 

Homolytic liquid-phase processes are generally well suited to the synthesis of carboxylic acids, viz. acetic, benzoic or terephthalic acids which are resistant to further oxidation. These processes operate at high temperature (150-250°C) and generally use soluble cobalt or manganese salts as the main catalyst components. High conversions and selectivities are usually obtained with methyl-substituted aromatic hydrocarbons such as toluene and xylenes.95,96 The cobalt-catalyzed oxidation of cyclohexane by air to a cyclohexanol-cyclohexanone mixture is a very important industrial process since these products are intermediates in the manufacture of adipic acid (for nylon 6,6) and caprolactam (nylon 6). However, the conversion is limited to ca. 10% in order to prevent consecutive oxidations, with roughly 70% selectivity.97... 

The significance of the reaction of phenol with hydrogen has a number of important facets. First, the selective hydrogenation of phenol yields cyclohexanone, which is a key raw material in the production of both caprolactam for nylon 6 and adipic acid for nylon 6 . Second, due to the fact that phenol is an environmental toxin and phenolic waste has a variety of origins from industrial sources including oil refineries, petrochemical units, polymeric resin manufacturing and plastic units , catalytic hydrogenation of phenol is nowadays the best practicable environmental option . ... 

OTHER COMMENTS used in the preparation of cyclohexanaone resins used as a solvent for cellulose acetate, nitrocellulose, natural resins, vinyl resins, crude rubber, waxes, fats, shellac, and dichlorodiphenyltrichlorooethane (DDT) used in organic synthesis, particularly in the production of adipic acid for nylon used in wood stains, paint and varnish removers, spot removers, metal degreasers, polishes, and as an additive for lubricating oils. 

Cyclohexanone - hek-so- non (ca. 1909) (pimelic ketone, ketohexamethylene) n. CH2(CH2)4C=0. a colorless liquid produced by the oxidation of cyclohexane or cyclohexanol. Its most important use is for the manufacturer of adipic acid for nylon 6/6, and caprolactam for nylon 6. It is also an excellent high-boiling, slowly evaporating solvent for many resins including cellulosics, acrylics and vinyls. It is one of the most powerful solvents for PVC, and is often used in lacquers to improve their adhesion to PVC (See image). 

Coriander (Coriandrum sativum L.) is an herbaceous crop widely grown for the herb cilantro and for coriander seed, a common spice (Evangelista et al., 2015). The seed contains oil consisting of 57-75% petroselinic acid (Fig. 11.11.1), 6-cw-octadecenoic acid (Isbell, 2009). Ozonolysis of petrosele-nic acid would produce lauric acid (C12 0) for use in surfactants and adipic acid for Nylon 6,6 (Millam et al., 1997). The seed produces 12.8-30.2% oil with yields averaging 900-1120 up to 2800 kg/ha but has yet to achieve success as an oilseed crop (Isbell, 2009). Attempts to engineer petroselinic acid production in transgenic crops have also proven problematic (Suh et al., 2002). 

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