Catalytic plants

Continuous processes have been developed for the alcohols, operating under pressure with Hquid ammonia as solvent. Potassium hydroxide (206) or anion exchange resins (207) are suitable catalysts. However, the relatively small manufacturing volumes militate against continuous production. For a while a continuous catalytic plant operated in Raveima, Italy, designed to produce about 40,000 t/yr of methylbutynol for conversion to isoprene (208,209). 

Fu, A., et al, Deep Catalytic Plant Ffi oduces Propylene in Thailand. Oil Gas Journal, January 12, 1998. 

Acetic acid Chemical CH3OH and CO-catalytic plants 10 6 650 0,68... 

Bernard, J. R., Santos-Cottin, H., and Margrita, R., Use of Radioactive Tracers for Studies on Fluidized Cracking Catalytic Plants , Isotopenpraxis, 25 (4), 161(1989). 

H02C(CH2)2C02H. Colourless prisms m.p. 182 C, b.p. 235°C. Occurs in amber, algae, lichens, sugar cane, beets and other plants, and is formed during the fermentation of sugar, tartrates, malates and other substances by a variety of yeasts, moulds and bacteria. Manufactured by the catalytic reduction of maleic acid or by heating 1,2-dicyanoethane with acids or alkalis. Forms an anhydride when heated at 235°C. Forms both acid and neutral salts and esters. Used in the manufacture of succinic anhydride and of polyesters with polyols. 

In a single stage, without liquid recycle, the conversion can be optimized between 60 and 90%. The very paraffinic residue is used to make lubricant oil bases of high viscosity index in the range of 150 N to 350 N the residue can also be used as feedstock to steam cracking plants providing ethylene and propylene yields equal to those from paraffinic naphthas, or as additional feedstock to catalytic cracking units. 

Patents claiming specific catalysts and processes for thek use in each of the two reactions have been assigned to Japan Catalytic (45,47—49), Sohio (50), Toyo Soda (51), Rohm and Haas (52), Sumitomo (53), BASF (54), Mitsubishi Petrochemical (56,57), Celanese (55), and others. The catalysts used for these reactions remain based on bismuth molybdate for the first stage and molybdenum vanadium oxides for the second stage, but improvements in minor component composition and catalyst preparation have resulted in yields that can reach the 85—90% range and lifetimes of several years under optimum conditions. Since plants operate under more productive conditions than those optimum for yield and life, the economically most attractive yields and productive lifetimes maybe somewhat lower. 

The first commercial production of fatty alcohol ia the 1930s employed the sodium reduction process usiug a methyl ester feedstock. The process was used ia plants constmcted up to about 1950, but it was expensive, hazardous, and complex. By about 1960 most of the sodium reduction plants had been replaced by those employing the catalytic hydrogenolysis process. Catalytic hydrogenation processes were investigated as early as the 1930s by a number of workers one of these is described ia reference 26. 

Secondary alcohols (C q—for surfactant iatermediates are produced by hydrolysis of secondary alkyl borate or boroxiae esters formed when paraffin hydrocarbons are air-oxidized ia the presence of boric acid [10043-35-3] (19,20). Union Carbide Corporation operated a plant ia the United States from 1964 until 1977. A plant built by Nippon Shokubai (Japan Catalytic Chemical) ia 1972 ia Kawasaki, Japan was expanded to 30,000 t/yr capacity ia 1980 (20). The process has been operated iadustriaHy ia the USSR siace 1959 (21). Also, predominantiy primary alcohols are produced ia large volumes ia the USSR by reduction of fatty acids, or their methyl esters, from permanganate-catalyzed air oxidation of paraffin hydrocarbons (22). The paraffin oxidation is carried out ia the temperature range 150—180°C at a paraffin conversion generally below 20% to a mixture of trialkyl borate, (RO)2B, and trialkyl boroxiae, (ROBO). Unconverted paraffin is separated from the product mixture by flash distillation. After hydrolysis of residual borate esters, the boric acid is recovered for recycle and the alcohols are purified by washing and distillation (19,20). 

Properties. Table 4 contains typical gasoline quaUty data from the New Zealand plant (67). MTG gasoline typically contains 60 vol % saturates, ie, paraffins and naphthenes 10 vol % olefins and 30 vol % aromatics. Sulfur and nitrogen levels in the gasoline are virtually lul. The MTG process produces ca 3—7 wt % durene [95-93-2] (1,2,4,5-tetra-methylbenzene) but the level is reduced to ca 2 wt % in the finished gasoline product by hydrodealkylation of the durene in a separate catalytic reactor. 

The MTO process employs a turbulent fluid-bed reactor system and typical conversions exceed 99.9%. The coked catalyst is continuously withdrawn from the reactor and burned in a regenerator. Coke yield and catalyst circulation are an order of magnitude lower than in fluid catalytic cracking (FCC). The MTO process was first scaled up in a 0.64 m /d (4 bbl/d) pilot plant and a successfiil 15.9 m /d (100 bbl/d) demonstration plant was operated in Germany with U.S. and German government support. 

Dehydrogenation. Dehydrogenation of / -butane was once used to make 1,3-butadiene, a precursor for synthetic mbber. There are currently no on-purpose butadiene plants operating in the United States butadiene is usually obtained as a by-product from catalytic cracking units. 

In the former USSR, there reportedly are two technologies in use one is old anthrahydroquinone autoxidation technology and the other is closed-loop isopropyl alcohol oxidation technology. Production faciUties include several smaller, 100-150-t/yr isopropyl alcohol oxidation plants and a larger, 15,000-t/yr plant, which reportedly is being expanded to 30,000-t/yr. Differences in this technology as compared to the Shell Chemical Co. process are the use of oxygen-enriched air in the oxidation step and, catalytic reduction of the coproduct acetone back to isopropyl alcohol per equation 21. 

A production plant for salt-free ethyleneimine synthesis by catalytic dehydration of monoethanol amine [141-45-5] in the gas phase has started operation at the Japanese company Nippon Shokubai (366). 

The purified raw gas goes to a Synthol (Eischer-Tropsch) unit for catalytic conversion of CO and H2 to Hquid fuels. The tars and oils obtained from quenching the raw gas from the gasifiers go to a Phenosolvan plant to provide tar products for the refinery and ammonia for fertilizer. The Synthol plant has seven reactors, each with 1.9 x 10 m /h (1.6 x 10 ft /d) gas feed. Annual plant production is 1.5 x 10 t motor fuels, 185 x 10 t ethylene,... 

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