Catalytic reforming is a chemical process used to convert petroleum refinery naphthas, typically having low octane ratings, into high-octane liquid products called reformates which are components of high-octane gasoline (also known as petrol). Basically, the process re-arranges or re-structures the hydrocarbon molecules in the naphtha feedstocks as well as breaking some of the molecules into smaller molecules. The overall effect is that the product reformate contains hydrocarbons with more complex molecular shapes having higher octane values than the hydrocarbons in the naphtha feedstock. In so doing, the process separates hydrogen atoms from the hydrocarbon molecules and produces very signicant amounts of byproduct hydrogen gas for use in a number of the other processes involved in a modern petroleum refinery. Other byproducts are small amounts of methane, ethane, propane and butanes. View of the Shell/Valero Martinez oil refinery An oil refinery is an industrial process plant where crude oil is processed and refined into useful petroleum products. ... Naphtha is a group of various volatile flammable liquid hydrocarbon mixtures used primarily as feedstocks in refineries for the reforming process and in the petrochemical industry for the production of olefins in steam crackers. ... A gas station pump offering five different octane ratings. ... Gasoline is a petroleum-derived liquid mixture consisting mostly of hydrocarbons and enhanced with benzene or iso-octane to increase octane ratings, used as fuel in internal combustion engines. ... Hydrocarbons are refined at oil refineries and processed at chemical plants A hydrocarbon is a chemical compound that consists only of the elements carbon (C) and hydrogen (H). ... In science, a molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ... A feedstock is a petrochemical used as a raw material to be fed into a machine or processing plant. ... This article is about the chemistry of hydrogen. ... Properties For alternative meanings see atom (disambiguation). ... Methane is a chemical compound with the molecular formula CH4. ... Ethane is a chemical compound with chemical formula C2H6. ... Propane is a three-carbon alkane, normally a gas, but compressible to a liquid that is transportable. ... Butane, also called n-butane, is the unbranched alkane with four carbon atoms, CH3CH2CH2CH3. ...

This process is quite different from and not to be confused with the catalytic steam reforming process used industrially to produce various products such as hydrogen, ammonia and methanol from natural gas, naphtha or other petroleum-derived feedstocks. Nor is this process to be confused with various other catalytic reforming processes that use methanol or biomass-derived feedstocks to produce hydrogen for fuel cells or other uses. Steam reforming, hydrogen reforming or catalytic oxidation, is a method of producing hydrogen from hydrocarbons. ... Ammonia is a compound with the formula NH3. ... Methanol, also known as methyl alcohol, wood alcohol or wood spirits, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid with a distinctive odor that is somewhat milder and sweeter than ethanol (ethyl alcohol). ... Switchgrass, a hardy plant used in the biofuel industry in the United States Rice chaff. ... A fuel cell is an electrochemical device similar to a battery, but differing from the latter in that it is designed for continuous replenishment of the reactants consumed; i. ...

History

Universal Oil Products (also known as UOP) is a multi-national company developing and delivering technology to the petroleum refining, natural gas processing, petrochemical production and other manufacturing industries. In the 1940s, an eminent research chemist named Vladimir Haensel^[1] working for UOP developed a catalytic reforming process using a catalyst containing platinum. Haensel's process was subsequently commercialized by UOP in 1949 for producing a high octane gasoline from low octane naphthas and the UOP process become known as the Platforming process.^[2] The first Platforming unit was built in 1949 at the refinery of the Old Dutch Refining Company in Muskegon, Michigan. UOP LLC, formerly known as Universal Oil Products, is a multi-national company developing and delivering technology to the petroleum refining, gas processing, petrochemical production and major manufacturing industries. ... View of Shell Oil Refinery in Martinez, California. ... Natural gas is a gaseous fossil fuel consisting primarily of methane but including significant quantities of ethane, butane, propane, carbon dioxide, nitrogen, helium and hydrogen sulfide. ... Petrochemicals are chemical products made from raw materials of petroleum (hydrocarbon) origin. ... In chemistry and biology, catalysis (in Greek meaning to annul) is the acceleration of the rate of a chemical reaction by means of a substance, called a catalyst, that is itself unchanged chemically by the overall reaction. ... It has been suggested that this article or section be merged into Catalysis. ... General Name, Symbol, Number platinum, Pt, 78 Chemical series transition metals Group, Period, Block 10, 6, d Appearance grayish white Atomic mass 195. ... Muskegon is a city located in Muskegon County, Michigan. ... Official language(s) None (English, de-facto) Capital Lansing Largest city Detroit Area  Ranked 11th  - Total 97,990 sq mi (253,793 km²)  - Width 239 miles (385 km)  - Length 491 miles (790 km)  - % water 41. ...

In the years since then, many other versions of the process have been developed by some of the major oil companies and other organizations. Today, the large majority of gasoline produced worldwide is derived from the catalytic reforming process.

To name a few of the other catalytic reforming versions that were developed, all of which utilized a platinum and/or a rhenium catalyst: General Name, Symbol, Number rhenium, Re, 75 Chemical series transition metals Group, Period, Block 7, 6, d Appearance grayish white Atomic mass 186. ...

• Rheniforming: Developed by Chevron Oil Company.
• Powerforming: Developed by Esso Oil Company, now known as Exxon.
• Magnaforming: Developed by Englehard Catalyst Company and Atlantic Richfield Oil Company.
• Ultraforming: Developed by Standard Oil of Indiana, now a part of the British Petroleum Company.
• Houdriforming: Developed by the Houdry Process Corporation.
• CCR Platforming: A Platforming version, designed for continuous catalyst regeneration, developed by UOP.
• Octanizing: A catalytic reforming version developed by Axens, a subsidiary of Institut francais du petrole (IFP), designed for continuous catalyst regeneration.

Chevron Corporation (NYSE: CVX) is one of the worlds largest global energy companies. ... An Esso Station in Stabekk, Norway An Esso-branded service station, with On the Run convenience store, in Kanata, Ontario. ... Exxon Mobil Corporation or ExxonMobil (NYSE: XOM), headquartered in Irving, Texas, is an oil producer and distributor formed on November 30, 1999, by the merger of Exxon and Mobil. ... An ARCO gas station in Los Angeles ARCO (an acronym for Atlantic Richfield Company) is an American oil company that was formed by the merger of East Coast-based Atlantic Refining and California-based Richfield Petroleum in 1966. ... Amoco was a United States oil company formed from the dissolution of Standard Oil. ... This article is about the corporation known as BP. See also BP (disambiguation) BP (formerly British Petroleum and briefly known as BP Amoco) (NYSE: BP) is a petroleum company headquartered in London, United Kingdom. ... The Institut français du pétrole (IFP, French Institute of Oil) is an independent research organisation in France. ...

Chemistry

Before describing the reaction chemistry of the catalytic reforming process as used in petroleum refineries, the typical naphthas used as catalytic reforming feedstocks will be discussed.

Typical naphtha feedstocks

A petroleum refinery includes many unit operations and unit processes. The first unit operation in a refinery is the continuous distillation of the petroleum crude oil being refined. The overhead liquid distillate is called naphtha and will become a major component of the refinery's gasoline (petrol) product after it is further processed through a catalytic hydrodesulfurizer to remove sulfur-containing hydrocarbons and a catalytic reformer to reform its hydrocarbon molecules into more complex molecules with a higher octane rating value. The naphtha is a mixture of very many different hydrocarbon compounds. It has an initial boiling point of about 35 °C and a final boiling point of about 200 °C, and it contains paraffin, naphthene (cyclic paraffins) and aromatic hydrocarbons ranging from those containing 4 carbon atoms to those containing about 10 or 11 carbon atoms. Unit operation is the basic principle of chemical engineering. ... Unit processing is the basic processing in chemical engineering. ... Continuous distillation is a distillation process, which does not require interruption for adding raw material. ... Pumpjack pumping an oil well near Sarnia, Ontario Ignacy Łukasiewicz - inventor of the refining of kerosene from crude oil. ... Hydrodesulfurization is one means of lowering the sulfur content of liquids from oil/coal. ... General Name, Symbol, Number sulfur, S, 16 Chemical series nonmetals Group, Period, Block 16, 3, p Appearance lemon yellow Atomic mass 32. ... The boiling point of a substance is the temperature at which it can change its state from a liquid to a gas throughout the bulk of the liquid at a given pressure. ... Paraffin is a common name for a group of alkane hydrocarbons with the general formula CnH2n+2, where n is greater than about 20, discovered by Carl Reichenbach. ... Cycloalkanes are chemical compounds with a one or more rings of carbons to which hydrogens are attached according to the formula CnH2n. ... In chemistry, an aromatic molecule is one in which electrons are free to cycle around circular arrangements of atoms, which are alternately singly and doubly bonded to one another. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ...

The naphtha from the crude oil distillation is often further distilled to produce a "light" naphtha containing most (but not all) of the hydrocarbons with 6 or less carbon atoms and a "heavy" naphtha containing most (but not all) of the hydrocarbons with more than 6 carbon atoms. The heavy naphtha has an initial boiling point of about 140 to 150 °C and a final boiling point of about 190 to 205 °C. The naphthas derived from the distillation of crude oils are referred to as "straight-run" naphthas.

It is the straight-run heavy naphtha that is usually processed in a catalytic reformer because the light naphtha has molecules with 6 or less carbon atoms which, when reformed, tend to crack into butane and lower molecular weight hydrocarbons which are not useful as high-octane gasoline blending components. Also, the molecules with 6 carbon atoms tend to form aromatics which is undesirable because governmental environmental regulations in a number of countries limit the amount of aromatics (most particularly benzene) that gasoline may contain.^[3][4][5] Benzene, also known as benzol, is an organic chemical compound with the formula C6H6. ...

It should be noted that there are a great many petroleum crude oil sources worldwide and each crude oil has its own unique composition or "assay". Also, not all refineries process the same crude oils and each refinery produces its own straight-run naphthas with their own unique initial and final boiling points. In other words, naphtha is a generic term rather than a specific term. This list of oil fields includes major fields of the past and present. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Look up Generic in Wiktionary, the free dictionary. ...

The table just below lists some fairly typical straight-run heavy naphtha feedstocks, available for catalytic reforming, derived from various crude oils. It can be seen that they differ significantly in their content of paraffins, naphthenes and aromatics:

Typical Heavy Naphtha Feedstocks

Crude oil name Location	Barrow Island Australia[6]	Mutineer-Exeter Australia[7]	CPC Blend Kazakhstan[8]	Draugen North Sea[9]
Initial boiling point, °C	149	140	149	150
Final boiling point, °C	204	190	204	180
Paraffins, liquid volume %	46	62	57	38
Naphthenes, liquid volume %	42	32	27	45
Aromatics, liquid volume %	12	6	16	17

Some refinery naphthas include olefinic hydrocarbons, such as naphthas derived from the fluid catalytic cracking and coking processes used in many refineries. Some refineries may also desulfurize and catalytically reform those naphthas. However, for the most part, catalytic reforming is mainly used on the straight-run heavy naphthas, such as those in the above table, derived from the distillation of crude oils. An alkene in organic chemistry is an unsaturated hydrocarbon containing at least one carbon to carbon double bond. ... In petroleum geology and chemistry, cracking is the process whereby complex organic molecules (e. ... This page is a candidate to be moved to Wiktionary. ... Hydrodesulfurization is one means of lowering the sulfur content of liquids from oil/coal. ...

The reaction chemistry

There are a good many chemical reactions that occur in the catalytic reforming process, all of which occur in the presence of a catalyst and a high partial pressure of hydrogen. Depending upon the type or version of catalyic reforming used as well as the desired reaction severity, the reaction conditions range from temperatures of about 495 to 525 °C and from pressures of about 5 to 45 atm.^[10] In a mixture of ideal gases, each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume. ... View of Jupiters active atmosphere, including the Great Red Spot. ...

The commonly used catalytic reforming catalysts contain noble metals such as platinum and/or rhenium, which are very susceptible to poisoning by sulfur and nitrogen compounds. Therefore, the naphtha feedstock to a catalytic reformer is always pre-processed in a hydrodesulfurization unit which removes both the sulfur and the nitrogen compounds. Noble metals are metals that are resistant to corrosion or oxidation, unlike most base metals. ... Catalyst poisoning refers to the effect that a catalyst can be poisoned if it reacts with another compound that bonds chemically (similar to an inhibitor) but does not release, or chemically alters the catalyst. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless gas Atomic mass 14. ... Hydrodesulfurization is one means of lowering the sulfur content of liquids from oil/coal. ...

The four major catalytic reforming reactions are:^[11]

1: The dehydrogenation of naphthenes to convert them into aromatics as exemplified in the conversion methylcyclohexane (a naphthene) to toluene (an aromatic), as shown below:

2: The isomerization of normal paraffins to isoparaffins as exemplified in the conversion of normal octane to 2,5-Dimethylhexane (an isoparaffin), as shown below:

3: The dehydrogenation and aromatization of paraffins to aromatics (commonly called dehydrocyclization) as exemplified in the conversion of normal heptane to toluene, as shown below:

4: The hydrocracking of paraffins into smaller molecules as exemplified by the cracking of normal heptane into isopentane and ethane, as shown below:

The hydrocracking of paraffins is the only one of the above four major reforming reactions that consumes hydrogen. The isomerization of normal paraffins does not consume or produce hydrogen. However, both the dehydrogenation of naphthenes and the dehydrocyclization of paraffins produce hydrogen. The overall net production of hydrogen in the catalytic reforming of petroleum naphthas ranges from about 50 to 200 cubic meters of hydrogen gas (at 0 °C and 1 atm) per cubic meter of liquid naphtha feedstock. In the United States customary units, that is equivalent to 300 to 1200 cubic feet of hydrogen gas (at 60 °F and 1 atm) per barrel of liquid naphtha feedstock.^[12] In many petroleum refineries, the net hydrogen produced in catalytic reforming supplies a significant part of the hydrogen used elsewhere in the refinery (for example, in hydrodesulfurization processes). Hydrogenation is a chemical reaction in which unsaturated bonds between carbon atoms are reduced by attachment of a hydrogen atom to each carbon. ... Toluene, also known as methylbenzene or phenylmethane is a clear, water-insoluble liquid with the typical smell of paint thinners, redolent of the sweet smell of the related compound benzene. ... Image File history File links No higher resolution available. ... In chemistry, isomerization is the transformation of a molecule into a different isomer. ... An alkane in organic chemistry is a type of hydrocarbon in which the molecule has the maximum possible number of hydrogen atoms and so has no double bonds (they are saturated). ... R-phrases , , , , S-phrases , , , , , , , Flash point 13 °C Autoignition temperature 220 °C Explosive limits 1. ... Image File history File links No higher resolution available. ... In chemistry, an aromatic molecule is one in which a conjugated ring of unsaturated bonds, lone pairs, or empty orbitals exhibit a stabilization stronger than would be expected by the stabilization of conjugation alone. ... R-phrases , , , , S-phrases , , , , , , , Flash point −4 °C Autoignition temperature 285 °C Explosive limits 1. ... Image File history File links No higher resolution available. ... In petroleum geology and chemistry, cracking is the process whereby complex organic molecules (e. ... Pentane also known as amyl hydride or skellysolve is an alkane hydrocarbon with the chemical formula CH3(CH2)3CH3. ... Image File history File links No higher resolution available. ... The cubic metre (symbol m³) is the SI derived unit of volume. ... U.S. customary units, commonly known in the United States as English units—but see English unit—or standard units, are units of measurement that are currently used in the USA, in some cases alongside units from SI (the International System of Units—the modern metric system). ... It has been suggested that Thousand Cubic Feet be merged into this article or section. ... The barrel is the name of several units of measurement. ...

Process description

The most commonly used type of catalytic reforming unit has three reactors, each with a fixed bed of catalyst, and all of the catalyst is regenerated in situ during routine catalyst regeneration shutdowns which occur approximately once each 6 to 24 months. Such units are referred to as semi-regenerative catalytic reformers. In chemical engineering, chemical reactors are vessels designed to contain chemical reactions. ... In situ is a Latin phrase meaning in the place. ... The phrase or term shut down, shut-down or shutdown can be used to mean turning off something, but most commonly used for machines or industrial plants such as computers, engines, nuclear reactors, petroleum refineries, fossil fuel power plants, and petrochemical plants. ...

Some catalytic reforming units have an extra spare or swing reactor and each reactor can be individually isolated so that any one reactor can be undergoing in situ regeneration while the other reactors are in operation. When that reactor is regenerated, it replaces another reactor which, in turn, is isolated so that it can then be regenerated. Such units, referred to as cyclic catalytic reformers, are not very common. Cyclic catalytic reformers serve to extend the period between required shutdowns.

The latest and most modern type of catalytic reformers are called continuous catalyst regeneration (CCR) reforming units. CCR units are characterized by continuous in situ regeneration of part of the catalyst in a special regenerator, and by continuous addition of the regenerated catalyst to the operating reactors. As of 2006, two CCR versions available: UOP's CCR Platformer process^[13] and Axen's Octanizing process.^[14] The installation and use of CCR units is rapidly increasing.

Many of the earliest catalytic reforming units (in the 1950's and 1960's) were non-regenerative in that they did not perform in situ catalyst regeneration. Instead, when needed, the aged catalyst was replaced by fresh catalyst and the aged catalyst was shipped to catalyst manufacturer's to be either regenerated or to recover the platinum content of the aged catalyst. Very few, if any, catalytic reformers currently in operation are non-regenerative.

The process flow diagram below depicts a typical semi-regenerative catalytic reforming unit. We dont have an article called Process flow diagram Start this article Search for Process flow diagram in. ...

Schematic diagram of a typical semi-regenerative catalytic reformer unit in a petroleum refinery

The liquid feed (at the bottom left in the diagram) is pumped up to the reaction pressure (5 to 45 atm) and is joined by a stream of hydrogen-rich recycle gas. The resulting liquid-gas mixture is preheated by flowing through a heat exchanger. The preheated feed mixture is then totally vaporized and heated to the reaction temperature (495 to 520 °C) before the vaporized reactants enter the first reactor. As the vaporized reactants flow through the fixed bed of catalyst in the reactor, the major reaction is the dehydrogenation of naphthenes to aromatics (as described earlier herein) which is highly endothermic and results in a large temperature decrease between the inlet and outlet of the reactor. To maintain the required reaction temperature and the rate of reaction, the vaporized stream is reheated in the second fired heater before it flows through the second reactor. The temperature again decreases across the second reactor and the vaporized stream must again be reheated in the third fired heater before it flows through the third reactor. As the the vaporized stream proceeds through the three reactors, the reaction rates decrease and the reactors therefore become larger. At the same time, the amount of reheat required between the reactors becomes smaller. Usually, three reactors are all that is required to to provide the desired performance of the catalytic reforming unit. Image File history File links No higher resolution available. ... An electrically driven pump (electropump) for waterworks near the Hengsteysee, Germany. ... A heat exchanger is a device built for efficient heat transfer from one fluid to another, whether the fluids are separated by a solid wall so that they never mix, or the fluids are directly contacted. ... Evaporation is the process whereby atoms or molecules in a liquid state (or solid state if the substance sublimes) gain sufficient energy to enter the gaseous state. ... In thermodynamics, the word endothermic describes a process or reaction that absorbs energy in the form of heat. ...

Some installations use three separate fired heaters as shown in the schematic diagram and some installations use a single fired heater with three separate heating coils.

The hot reaction products from the third reactor are partially cooled by flowing through the heat exchanger where the feed to the first reactor is preheated and then flow through a water-cooled heat exchanger before flowing through the pressure controller (PC) into the gas separator.

Most of the hydrogen-rich gas from the gas separator vessel returns to the suction of the recycle hydrogen gas compressor and the net production of hydrogen-rich gas from the reforming reactions is exported for use in other the other refinery processes that consume hydrogen (such as hydrodesulfurization units and/or a hydrocracker unit). A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume. ... In petroleum geology and chemistry, cracking is the process whereby complex organic molecules (e. ...

The liquid from the gas separator vessel is routed into a fractionating column commonly called a stabilizer. The overhead offgas product from the stabilizer contains the byproduct methane, ethane, propane and butane gases produced by the hydrocracking reactions as explained in the above discussion of the reaction chemistry of a catalytic reformer, and it may also contain some small amount of hydrogen. That offgas is routed to the refinery's central gas processing plant for removal and recovery of propane and butane. The residual gas after such processing becomes part of the refinery's fuel gas system. A fractionating column is an essential item used in the distillation of liquid mixtures so as to separate the mixture into its component parts, or fractions, based on the differences in their volatilities. ...

The bottoms product from the stabilizer is the high-octane liquid reformate that will become a component of the refinery's product gasoline.

Catalysts and mechanisms

Most catalytic reforming catalysts contain platinum or rhenium on a silica or silica-alumina support base, and some contain both platinum and rhenium. Fresh catalyst is chlorided (chlorinated) prior to use. R-phrases R42 R43 R49 S-phrases S22 S36 S37 S45 S53 Flash point non-flammable Supplementary data page Structure and properties n, εr, etc. ... Aluminium oxide (or aluminum oxide) (Al2O3) is a chemical compound of aluminium and oxygen. ... The chloride ion is formed when the element chlorine picks up one electron to form an anion (negatively-charged ion) Cl−. The salts of hydrochloric acid HCl contain chloride ions and are also called chlorides. ...

The noble metals (platinum and rhenium) are considered to be catalytic sites for the dehydrogenation reactions and the chlorinated alumina provides the acid sites needed for isomerization, cyclization and hydrocracking reactions.^[11] Acidity redirects here. ...

The activity (i.e., effectiveness) of the catalyst in a semi-regenerative catalytic reformer is reduced over time during operation by carbonaceous coke deposition and chloride loss. The activity of the catalyst can be periodically regenerated or restored by in situ high temperature oxidation of the coke followed by chlorination. As stated earlier herein, semi-regenerative catalytic reformers are regenerated about once per 6 to 24 months. General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ...

Normally, the catalyst can be regenerated perhaps 3 or 4 times before it must be returned to the manufacturer for reclamation of the valuable platinum and/or rhenium content.^[11]

External links

• Oil Refinery Processes, A Brief Overview
• Colorado School of Mines, Lecture Notes (Chapter 10, Refining Processes, Catalytic Refinery by John Jechura, Adjunct Professor)
• Students' Guide to Refining] (scroll down to Platforming)
• Modern Refinery Website of Delft University of Technology, Netherlands (use search function for Reforming)
• Major scientific and technical challenges about development of new refining processes (IFP website)

Founded in 1842, the Delft University of Technology, in Delft, the Netherlands, is one of the oldest, largest, and most comprehensive technical universities in the Netherlands, with over 13,000 students and 2,100 scientists (including 200 professors). ...

References

1. ^ A Biographical Memoir of Vladimir Haensel written by Stanley Gembiki, published by the National Academy of Sciences in 2006.
2. ^ Platforming described on UOP's website
3. ^ Canadian regulations on benzene in gasoline
4. ^ United Kingdom regulations on benzene in gasoline
5. ^ USA regulations on benzene in gasoline
6. ^ Barrow Island crude oil assay
7. ^ Mutineer-Exeter crude oil assay
8. ^ CPC Blend crude oil assay
9. ^ Draugen crude oil assay
10. ^ OSHA Technical Manual, Section IV, Chapter 2, Petroleum refining Processes (A publication of the Occupational Safety and Health Administration)
11. ^ ^{a b c} Gary, J.H. and Handwerk, G.E. (1984). Petroleum Refining Technology and Economics, 2nd Edition, Marcel Dekker, Inc. ISBN 0-8247-7150-8. 
12. ^ US Patent 5011805, Dehydrogenation, dehydrocyclization and reforming catalyst (Inventor: Ralph Dessau, Assignee: Mobil Oil Corporation)
13. ^ CCR Platforming (UOP website)
14. ^ Octanizing Options (Axens website)