Commercial hydrocarbonization process

Interest in synthetic naphthenic acid has grown as the supply of natural product has fluctuated. Oxidation of naphthene-based hydrocarbons has been studied extensively (35—37), but no commercially viable processes are known. Extensive purification schemes must be employed to maximize naphthene content in the feedstock and remove hydroxy acids and nonacidic by-products from the oxidation product. Free-radical addition of carboxylic acids to olefins (38,39) and addition of unsaturated fatty acids to cycloparaffins (40) have also been studied but have not been commercialized. 

Polymerization in a hydrocarbon slurry (usually a light-saturated hydrocarbon) was the first commercial polymerization process to utilize Phillips and Ziegler catalysts. These processes enjoy high popularity because of theit versatihty. 

Hydroperoxide Process. The hydroperoxide process to propylene oxide involves the basic steps of oxidation of an organic to its hydroperoxide, epoxidation of propylene with the hydroperoxide, purification of the propylene oxide, and conversion of the coproduct alcohol to a useful product for sale. Incorporated into the process are various purification, concentration, and recycle methods to maximize product yields and minimize operating expenses. Commercially, two processes are used. The coproducts are / fZ-butanol, which is converted to methyl tert-huty ether [1634-04-4] (MTBE), and 1-phenyl ethanol, converted to styrene [100-42-5]. The coproducts are produced in a weight ratio of 3—4 1 / fZ-butanol/propylene oxide and 2.4 1 styrene/propylene oxide, respectively. These processes use isobutane (see Hydrocarbons) and ethylbenzene (qv), respectively, to produce the hydroperoxide. Other processes have been proposed based on cyclohexane where aniline is the final coproduct, or on cumene (qv) where a-methyl styrene is the final coproduct. 

Hydrocarbon—Sulfur Process. The principal commercial hydrocarbon is methane from natural gas, although ethane, and olefins such as propylene (45,46), have also been used. 

Activated alumina and phosphoric acid on a suitable support have become the choices for an iadustrial process. Ziac oxide with alumina has also been claimed to be a good catalyst. The actual mechanism of dehydration is not known. In iadustrial production, the ethylene yield is 94 to 99% of the theoretical value depending on the processiag scheme. Traces of aldehyde, acids, higher hydrocarbons, and carbon oxides, as well as water, have to be removed. Fixed-bed processes developed at the beginning of this century have been commercialized in many countries, and small-scale industries are still in operation in Brazil and India. New fluid-bed processes have been developed to reduce the plant investment and operating costs (102,103). Commercially available processes include the Lummus processes (fixed and fluidized-bed processes), Halcon/Scientific Design process, NIKK/JGC process, and the Petrobras process. In all these processes, typical ethylene yield is between 94 and 99%. 

The Institut Fran ais du Petrole has developed and commercialized a process, named Dimersol X, based on a homogeneous catalyst, which selectively produces dimers from butenes. The low-branching octenes produced are good starting materials for isononanol production. This process is catalyzed by a system based on a nickel(II) salt, soluble in a paraffinic hydrocarbon, activated with an alkylalumini-um chloride derivative directly inside the dimerization reactor. The reaction is sec-... 

Among the wide variety of organic reactions in which zeolites have been employed as catalysts, may be emphasized the transformations of aromatic hydrocarbons of importance in petrochemistry, and in the synthesis of intermediates for pharmaceutical or fragrance products.5 In particular, Friede 1-Crafts acylation and alkylation over zeolites have been widely used for the synthesis of fine chemicals.6 Insights into the mechanism of aromatic acylation over zeolites have been disclosed.7 The production of ethylbenzene from benzene and ethylene, catalyzed by HZSM-5 zeolite and developed by the Mobil-Badger Company, was the first commercialized industrial process for aromatic alkylation over zeolites.8 Other typical examples of zeolite-mediated Friedel-Crafts reactions are the regioselective formation of p-xylene by alkylation of toluene with methanol over HZSM-5,9 or the regioselective p-acylation of toluene with acetic anhydride over HBEA zeolites.10 In both transformations, the p-isomers are obtained in nearly quantitative yield. 

Sepasolv MPE [Methyl isopropyl ester] A variation on the Selexol process, using the methyl isopropyl ethers of polyethylene glycol as the solvent. Developed by BASF. Four commercial plants were operating in 1985, removing hydrogen sulfide from natural gas. Wolfer, W., Hydrocarbon Process., 1982,61(11), 193. 

Acrylonitrile Acrylonitrile is produced by reacting propylene, ammonia, and oxygen (air) in a single fluidized bed of a complex catalyst. Known as the SOHIO process, this process was first operated commercially in 1960. In addition to acrylonitrile, significant quantities of HCN and acetonitrile are produced. This process is also exothermic, and temperature control is achieved by raising steam inside vertical tubes immersed in the bed [Veatch, Hydrocarbon Process. Pet. Refiner 41 18 (November 1962)]. 

Organic solids have received much attention in the last 10 to 15 years especially because of possible technological applications. Typically important aspects of these solids are superconductivity (of quasi one-dimensional materials), photoconducting properties in relation to commercial photocopying processes and photochemical transformations in the solid state. In organic solids formed by nonpolar molecules, cohesion in the solid state is mainly due to van der Waals forces. Because of the relatively weak nature of the cohesive forces, organic crystals as a class are soft and low melting. Nonpolar aliphatic hydrocarbons tend to crystallize in approximately close-packed structures because of the nondirectional character of van der Waals forces. Methane above 22 K, for example, crystallizes in a cubic close-packed structure where the molecules exhibit considerable rotation. The intermolecular C—C distance is 4.1 A, similar to the van der Waals bonds present in krypton (3.82 A) and xenon (4.0 A). Such close-packed structures are not found in molecular crystals of polar molecules. 

Catalyst. In all of the commercial isomerization processes applied to paraffins and naphthenes, the catalyst is aluminum chloride plus hydrogen chloride. In the pure state, these two ingredients do not associate chemically (1), but they become associated in the presence of certain hydrocarbons normally occurring in petroleum stocks. 

This review is concerned with a discussion of the reactions of hydrocarbons over bifunctional catalysts, primarily from the viewpoint of mechanism and kinetics. Some discussion will also be given of the structure and properties of typical bifunctional reforming catalysts, since this is somewhat helpful in understanding how the catalyst functions in promoting the various reactions. In addition, at appropriate places in the article, the practical application of the principles of bifunctional catalysis in commercial reforming processes will be considered. 

Scaling Up from Laboratory Data Laboratory experimental techniques offer an efficient and cost-effective route to develop commercial absorption designs. For example, Ouwerkerk (Hydrocarbon Process., April 1978, 89-94) revealed that both laboratory and small-scale pilot plant data were employed as the basis for the design of an 8.5-m (28-ft) diameter commercial Shell Claus off-gas treating (SCOT) tray-type absorber. Ouwerkerk claimed that the cost of developing comprehensive design procedures can be minimized, especially in the development of a new process, by the use of these modern techniques. 

Because of its low cost, nonhazardous chemical nature, and low critical temperature, carbon dioxide has been used in many applications. A commercial process to remove caffeine from coffee, using supercritical C02 as the solvent, is shown in Fig. 17. While actually a liquid-solid extraction process, it demonstrates principles involved in SCFE. A commercial SCFE process has been reported for recovery of hydrocarbon liquid from heavy oil. As compared with conventional propane deasphalting, this SCFE process can reduce capital and energy costs. 

The heat of polymerization of ethylene is high (93.6 kJ/mol). Heat removal is thus a key issue in commercial polymerization processes. Polyolefins are produced primarily by suspension (slurry), gas-phase, or solution processes (20). Solution processes have been developed by various companies using hydrocarbons, such as heptane or cyclohexane, or hydrocarbon mixtures as solvents. The reaction temperature is in the range of 200-300°C. An advantage of these processes is that they readily accommodate a wide range of comonomer types and product densities. Like the high-pressure process, which is also a solution process, they are unable to accommodate highly viscous products. 

Figure 8.to Surfaces used in commercial corrugated structured packings, (a) Smooth, perforated (b) grooved, perforated (c) lanced, perforated. parts a to c, from G. K. Chen and K. T. Chuang, Hydrocarbon, Trvo February, 1989, p. 97, reproduced courtesy of Hydrocarbon Processing.)... 

Masumone, S., Kawatani. T., First commercial MHC unit onstream . Hydrocarbon Processing, 47 (12)... 

In the November 1965 Hydrocarbon Processing and Petroleum Refiner (17), it was indicated that the first commercial plant for such a process was being installed by Cities Service for start-up in late 1966, under license from Texaco Development Corporation. 

Various catalysts used in the two processes have been described as follows zeolite, alumina, silica-alumina, FCC catalyst, reforming catalyst, and others. The most common catalysts used in the cracking of heavy hydrocarbons are acidic catalysts alumina and silica-alumina with mesopores, and also zeolite with micropores, etc. They are typically used in the commercial petroleum process. For the chemical properties of catalyst, the... 

Details of process instruments and control equipment can be found in various handbooks see Perry and Green (1997) and Liptak (2003). Reviews of process instruments and control equipment are published periodically in the journals Chemical Engineering and Hydrocarbon Processing. These reviews give details of instruments and control hardware available commercially. 

The heteroatom reactants do not themselveB deactivate the catalyst the catalyst deactivates due to coke formation from hydrocarbons and metal deposition from the mineral in coal. The commercial HT process cannot be easily carried out on a bench scale, because of materials handling and pressure pioblenis however, the process is carried out on a demonstration scale at the Advanced Coal Lique ction Research and Devdopment Facility at Wilsonville, AL. Small portions of the catalyst are removed at various deactivation levels, quantified as the weight of product per weight of catalyst, with the metals and coke deposits on the removed solid being characterized. 

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