Hydrocarbons catalytic reforming

Zaera F (2002) Selectivity in hydrocarbon catalytic reforming a surface chemistry perspective. Appl Catal A 229 75... 

Iron based catalyst for hydrocarbons catalytic reforming A metal-support interaction study to interpret reactivity data... 

Cyclic Hydrocarbons. The cyclic hydrocarbon intermediates are derived principally from petroleum and natural gas, though small amounts are derived from coal. Most cycHc intermediates are used in the manufacture of more advanced synthetic organic chemicals and finished products such as dyes, medicinal chemicals, elastomers, pesticides, and plastics and resins. Table 6 details the production and sales of cycHc intermediates in 1991. Benzene (qv) is the largest volume aromatic compound used in the chemical industry. It is extracted from catalytic reformates in refineries, and is produced by the dealkylation of toluene (qv) (see also BTX Processing). 

Butanes are naturally occurring alkane hydrocarbons that are produced primarily in association with natural gas processing and certain refinery operations such as catalytic cracking and catalytic reforming. The term butanes includes the two stmctural isomers, / -butane [106-97-8] CH2CH2CH2CH2, and isobutane [79-28-9], (CH2)2CHCH2 (2-methylpropane). 

Mixtures of CO—H2 produced from hydrocarbons, as shown in the first two of these reactions, ate called synthesis gas. Synthesis gas is a commercial intermediate from which a wide variety of chemicals are produced. A principal, and frequendy the only source of hydrogen used in refineries is a by-product of the catalytic reforming process for making octane-contributing components for gasoline (see Gasoline and OTHER MOTOR fuels), eg. 

Plants have now been installed by some manufacturers to produce ethylbenzene via catalytic reforming processes. The reforming process is one which converts aliphatic hydrocarbons into a mixture of aromatic hydrocarbons. This may be subsequently fractionated to give benzene, toluene and a xylene fraction from which ethylbenzene may be obtained. 

Catalytic Reforming Heater stack gas (CO, SO, NO, HCs and PM), fugitive emissions (hydrocarbons) and catalyst regeneration (CO, NO, SO,). 

The primary process for separating the hydrocarbon components of crude oil is fractional distillation i.e. separation according to the boiling points of the components. These separated fractions are processed further by catalytic reformers, cracking units, alkylation units, or cokers which have there own fractional distillation towers for its products. 

J. J. Szakasits and R. E. Robinson, Hydrocarbon type determination of naphthas and catalytically reformed products hy automated multidimensional gas cliromatography . Anal. Chem. 63 114-120(1991). 

Benzene (CeHg) is the simplest aromatic hydrocarbon and by far the most widely used one. Before 1940, the main source of benzene and substituted benzene was coal tar. Currently, it is mainly obtained from catalytic reforming. Other sources are pyrolysis gasolines and coal liquids. 

Liquid solvents are used to extract either desirable or undesirable compounds from a liquid mixture. Solvent extraction processes use a liquid solvent that has a high solvolytic power for certain compounds in the feed mixture. For example, ethylene glycol has a greater affinity for aromatic hydrocarbons and extracts them preferentially from a reformate mixture (a liquid paraffinic and aromatic product from catalytic reforming). The raffinate, which is mainly paraffins, is freed from traces of ethylene glycol by distillation. Other solvents that could be used for this purpose are liquid sulfur dioxide and sulfolane (tetramethylene sulfone). 

Normally, catalytic reformers operate at approximately 500-525°C and 100-300 psig, and a liquid hourly space velocity range of 2-4 hr" Liquid hourly space velocity (LHSV) is an important operation parameter expressed as the volume of hydrocarbon feed per hour per unit volume of the catalyst. Operating at lower LHSV gives the feed more contact with the catalyst. 

In Europe naphtha is the preferred feedstock for the production of synthesis gas, which is used to synthesize methanol and ammonia (Chapter 4). Another important role for naphtha is its use as a feedstock for steam cracking units for light olefins production (Chapter 3). Heavy naphtha, on the other hand, is a major feedstock for catalytic reforming. The product reformate containing a high percentage of Ce-Cg aromatic hydrocarbons is used to make gasoline. Reformates are also extracted to separate the aromatics as intermediates for petrochemicals. 

The Ce-Cg aromatic hydrocarbons—though present in crude oil—are generally so low in concentration that it is not technically or economically feasible to separate them. However, an aromatic-rich mixture can be obtained from catalytic reforming and cracking processes, which can be further extracted to obtain the required aromatics for petrochemical use. Liquefied petroleum gases (C3-C4) from natural gas and refinery gas streams can also be catalytically converted into a liquid hydrocarbon mixture rich in C6-C8 aromatics. 

It can also be prepd by the catalytic reforming of other low-boiling hydrocarbons (ethane to butane) (Ref 3)... 

Cortright, R. D. Davda, R. R. Dumesic, J. A., Hydrogen from catalytic reforming of biomass-derived hydrocarbons in liquid water. Nature 2002,418,964. 

The bulk of the naphtha was hydrotreated and catalytically reformed over a chlorided Pt/Al203-based catalyst to produce an aromatic motor gasoline. However, the hydrotreated Fischer-Tropsch naphtha is a poor feed for standard catalytic reforming on account of its high linear hydrocarbon content (>75%).37 In order to limit liquid yield loss, typical operation resulted in a reformate with quite low octane value (Table 18.10). Higher octane reformate could be produced, but at the expense of significant liquid yield loss. 

Magnaforming A catalytic reforming process developed by the Atlantic Richfield Corporation and Englehard Corporation. First announced in 1965, it was commercialized in 1967 and by 1988, 150 units were operating worldwide. Hydrocarbon Research has installed units in Argentina, Algeria, and the USSR. 

Parex (1) [Para extraction] A version of the Sorbex process, for selectively extracting p-xylene from mixtures of xylene isomers, ethylbenzene, and aliphatic hydrocarbons. The feedstock is usually a C8 stream from a catalytic reformer, mixed with a xylene stream from a xylene isomerization unit. The process is operated at 177°C the desorbent is usually p-diethylbenzene. The first commercial plant began operation in Germany in 1971 by 1992, 453 plants had been licensed worldwide. Not to be confused with Parex (2). 

STAR [Steam Active Re-forming] A catalytic reforming process for converting aliphatic hydrocarbons to olefins or aromatic hydrocarbons. Hydrocarbons containing five or fewer carbon atoms are converted to olefins. Those containing six or more are dehydrocy-clized to aromatic hydrocarbons. The reactions take place in the vapor phase, in a fixed catalyst bed containing a noble metal catalyst, in the presence of steam. Demonstrated on a semi-commercial scale and offered for license by Phillips Petroleum Company. The first commercial plant was built for Coastal Chemicals in Cheyenne, WY, in 1992 another for Polibutenos Argentinos in 1996. 

UGI [United Gas Improvement Company Also called Ugite. A regenerative catalytic reforming process for making town gas and liquid hydrocarbons from oil. The catalyst was a fixed bed of hot, refractory pebbles. Developed by UGI Company, Philadelphia, PA, in the early 1940s. 

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