Amoco Chemicals

Purified terephthahc acid became commercially available from Amoco Chemical Co. in 1965, by which time a considerable polyester industry based on dimethyl terephthalate had already developed. The Amoco process involves purification of cmde terephthahc acid by a separate step to attain the high product purity required for polyester manufacture. The Amoco technology is the most-used worldwide, but other processes have been developed and are operating commercially. 

Worldwide capacity available for production of isophthahc acid was about 270 x 10 t in 1994. About 200 x 10 t was actually produced. Amoco Chemical with plants in the United States and Europe is the principal producer, with over 60% of the production, and AGIC, an Amoco—Mitsubishi Gas Chemical joint venture in Japan, and SISAS produce the remainder. 

Manufacture. The only current U.S. manufacturer of trimesic acid is Amoco Chemical Co. It is produced by oxidation of mesitylene (1,3,5-trimethylbenzene) via the Hquid-phase oxidation in acetic acid using the cobalt— manganese—bromine catalyst system (138). This is a variant of the system used to produce terephthaUc and isophthaUc acids as well as trimellitic anhydride. American Bio-Synthetics Corp. did produce it by batch oxidation of mesitylene with potassium permanganate. 

Specifications and Standards. Table 35 Hsts specifications for trimesic acid as produced by Amoco Chemical (139). Typically, the product is over 98% pure. 

The use of the Hquid-phase process in acetic acid with the cobalt— manganese—bromine system as explained in the tetephthaUc acid section is also possible (149). This process has been used by Amoco Chemical to produce pyromellitic acid, and facUities remain in place to do so again in the future. As with all hquid-phase oxidations of this type, yields ate high. A separate dehydration step would be needed to yield the dianhydtide. 

Production, Storage, and Shipment. As noted above, AUco Chemical, Amoco Chemical, Mitsubishi Gas Chemical, and Hbls all produce either the acid or the anhydride using different production techniques. The relatively small production volumes of pyromellitic acid and dianhydride results in both storage and shipment in polyethylene-lined fiber dmms of 22—136-kg capacity. 

D. H. Meyer, H. P. Pohlmann, and C. E. Johnson, "Production of Aromatic Acids by the Amoco Chemicals Corporation," Pacific Chemical... 

Material Safety Data Sheet, Amoco TA-33, Amoco Chemical Co., Chicago, hi., Dec. 1993. 

Chang-Man Park Richard J. Sheehan Amoco Chemical Company... 

Pseudocumene. The Hquid-phase air oxidation of pseudocumene yields trimeUitic acid [528-44-9] (15) which is dehydrated to trimeUitic anhydride [552-30-7] (TMA) (16). Amoco Chemical is the sole U.S. producer with a plant at JoHet, Illinois, having a capacity of ca 47,000 t/yr. Lonza ia Italy is the sole European TMA producer. 

Bulletin TAIN 27, Amoco Chemicals Corp., Chicago, lU. 

Most commercial processes produce polypropylene by a Hquid-phase slurry process. Hexane or heptane are the most commonly used diluents. However, there are a few examples in which Hquid propylene is used as the diluent. The leading companies involved in propylene processes are Amoco Chemicals (Standard OH, Indiana), El Paso (formerly Dart Industries), Exxon Chemical, Hercules, Hoechst, ICl, Mitsubishi Chemical Industries, Mitsubishi Petrochemical, Mitsui Petrochemical, Mitsui Toatsu, Montedison, Phillips Petroleum, SheU, Solvay, and Sumimoto Chemical. Eastman Kodak has developed and commercialized a Hquid-phase solution process. BASE has developed and commercialized a gas-phase process, and Amoco has developed a vapor-phase polymerization process that has been in commercial operation since early 1980. 

To R. A. Wilsak and M. E. Carrera (Amoco Chemical Co.) and O. C. Okoroafor (Cooper Union for the Advancement of Science and Arts). 

Although benzene prices have escalated in recent years, a concurrent need for butenes for use in alkylates for motor fuel has also increased and butane prices have also escalated. As a result, a search for alternative feedstocks began and Amoco Chemical Co. commercialized a process in 1977 to produce maleic anhydride from butane. A plant in JoHet came on-stream in 1977 with a capacity of 27,000 t/yr (135,136). No new plants have been built in the United States based on butenes since the commercialization of butane to maleic anhydride technology. In Europe and particularly in Japan, however, where butane is in short supply and needs for butenes as alkylation feed are also much less, butenes may become the dominant feedstock (see Maleic anhydride). 

C. Hoff, UK Im, W. F. Hauschildt, and 1. Puskas, Amoco Chemicals Company. 

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