Importance petroleum refining

Cumene or isopropylbenzene, diisopropylbenzene, and secondary butyl-benzene, although produced in smaller quantities than some of the other petrochemical alkylates, are very important petroleum refining products. Cumene is further reacted by oxidation to form cumene hydroperoxide, which is converted to phenol and acetone it is produced by alkylating benzene with propylene catalyzed by either solid or liquid phosphoric acid. Secondary butylbenzene is made by alkylating benzene with normal butylene using the same catalysts. Diisopropylbenzene is made by reacting cumene with propylene over solid phosphoric acid or aluminum chloride catalyst. 

There are many types, and only the most important can be mentioned here. [See also Hunter, in Dunstan (ed.). Science of Petroleum, vol. 3, Oxford, New York, 1938, pp. 1779-1797.] They are used fairly extensively in treating petroleum distillates, in vegetable-oil, refining, in extraction of phenol-bearing coke-oven liquors, in some met extractions, and the like. Kalichevsky and Kobe (Petroleum Refining... 

The powders of zeolites of various trademarks are used to produce petroleum-refining catalysts. In this connection, it is very important to have complete information concerning not only chemical composition and distribution of impurity elements, but also shape, surface, stmcture and sizes of particles. It allows a more detailed analysis of the physical-chemical characteristics of catalysts, affecting their activity at different stages of technological process. One prospective for solving these tasks is X-ray microanalysis with an electron probe (EPMA). 

When discussing material outputs of the petroleum refining industry, it is important to note the relationship between the outputs of the industry itself and the outputs resulting from the use of refmery products. Petroleum refineries play an important role in the U.S. economy, supplying approximately 40% of the total energy used in the U.S. and virtually all of the energy consumed in the transportation sector. 

There are many other processes used in refineries not mentioned here. The list above is intended only to emphasize the wide diversity of processing which is common to petroleum refining and to introduce in a very general way some of the more important of these processes. Also it must be emphasized that only fundamental principles of refinery operations have been discussed and modem manufacmring techniques vary widely from company to company. 

Distillation may be defined as the separation of the constituents of a liquid mixture by partial vaporization of the mixture, followed by separate recovery of the vapor and liquid residue. Since crude petroleum is the most complex mixture of liquids found in nature, it is not surprising that distillation is one of the most important processes in modem petroleum refining. 

Since the first synthesis of ammonia, catalyst development and chemical reaction engineering have been instrumental in the creation of the chemical process industry. As a result, catalytic processes have contributed much to the realization of prosperous civilizaticm. In the future, catalytic processes are expected to fulfill important roles in petroleum refining, diemical processing and environmental preservation. However, at present, many catalytic processes discharge large amounts of byproducts and consume large amounts of auxiliary raw materials. 

The performance of a supported metal or metal sulfide catalyst depends on the details of its preparation and pretreatraent. For petroleum refining applications, these catalysts are activated by reduction and/or sulfidation of an oxide precursor. The amount of the catalytic component converted to the active ase cind the dispersion of the active component are important factors in determining the catalytic performance of these materials. This investigation examines the process of reduction and sulfidation on unsupported 00 04 and silica-supported CO3O4 catalysts with different C03O4 dispersions. The C03O4 particle sizes were determined with electron microscopy. X-ray diffraction (XRD), emd... 

Hydrodenitrogenation (HDN) is an important process in petroleum refining. It removes nitrogen from oil distillates, so that less NOx pollutes the air when oil is burned and poisoning of the subsequent refining catalysts is reduced when the oil is processed further. Although HDN has been studied intensively and different reaction mechanisms, catalytic active sites, and functions of the catalytic components have been proposed, there are stiU many questions to be answered in order to better mderstand the reaction and the catalyst (1-4). 

The activity and decay behaviour of the different porous heteropolycompounds were compared in two reactions requiring strong acid sites the n-butane isomerization and the isobutane/2-butene alkylation. Although these two reactions are important in the petroleum refining industry, n-butane isomerization is often used as a "test reaction" since it is known that this reaction requires very strong acid sites and only a limited number of oxides are active in this reaction, under mild conditions (T = 473 K). 

Hydrofluoric acid is an important refrigerant and it is used as a bulking agent in foam industries. It is widely used in the aluminum production industry, nuclear fuel, steel, petroleum refining, and fluoride salt production. 

The aromatization of liquefied petroleum gases (LPG) has been investigated for more than a decade due to its economical and strategic importance for the exploitation of natural gas reserves and valorization of light hydrocarbons obtained from petroleum refining. Commercially, these reactions using gallium modified ZSM-5 zeolite catalysts are known as Cyclar process, developed jointly by UOP and BP [1]. 

The manufacture of fertilizers was discussed in Chapter 14. Phosphate rock is digested with sulfuric acid to convert CaC03 into a more soluble form that contains a higher percentage of phosphorus. Sulfuric acid is used as a catalyst in alkylation reactions, petroleum refining, manufacture of detergents, paints, dyes, and fibers, and other processes. It is also used as the electrolyte in the lead-acid battery that is used in automobiles. Sulfuric acid is an enormously important chemical commodity that it would be hard to do without. 

Zeolite molecular sieves are widely used as solid acid catalysts or catalyst components in areas ranging from petroleum refining to the synthesis of intermediates and fine chemicals (112,113). An important reason for their widespread use is the flexibility they oflFer regarding the tailoring of the concentration and nature of catalytically active sites and their immediate environments. We note that discrimination between chemical and structural aspects works well at a conceptual level, but one faces quite severe limitations as soon as one tries to separate the contributions of the two effects. The complexity arises because the chemical properties of a particular molecular sieve are connected with its framework density. 

They are not found to any extent in natural products, but are produced in the destructive distillation of complex natural substances, such as coal, and are formed in large amounts in petroleum refining, particularly in the cracking process. The first member of the series is ethylene, C2H4. The dienes contain two double bonds between pairs of carbon atoms in the molecule. They are related to the complex hydrocarbons in natural rubber and are important in the manufacture of synthetic rubber and plastics. The most important members of this series are butadiene, C4H5 and isoprene, CsHg. 

Benzene from coal coking started to become less important in the 1950s as the benzene market mushroomed considerably faster than the steel market, and the marginal supply of benzene came from petroleum refining. Coal-based benzene for the U.S. chemical industry dropped from nearly 100% in 1955 to 50% in the 1960s and less than 5% after the 1980s. Coal-based economies like South Africa and New Zealand sail rely considerably more on coal-derived benzene. 

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