The cracking and reforming of crude oil fractions presentation free download as powerpoint presentation. Crude oil is a major source of hydrocarbons that is used to produce fuels. Reforming involves changing the chemical nature of hydrocarbons to achieve desired physical properties and also to increase the market value. Alkenes are reactive molecules that are used to make plastics and other chemicals. Furthermore, it should be treated in order to obtain highly effective end products. Thermal cracking is the simplest and oldest process. Reforming, in chemistry, processing technique by which the molecular structure of a hydrocarbon is rearranged to alter its properties. For example, crude oil can be processed cracked to. The process is frequently applied to lowquality gasoline stocks to improve their combustion characteristics. Us2347527a us372007a us37200740a us2347527a us 2347527 a us2347527 a us 2347527a us 372007 a us372007 a us 372007a us 37200740 a us37200740 a us 37200740a us 2347527 a us2347527 a us 2347527a authority us united states prior art keywords cracking hydrogen tubes carbon hydrocarbons prior art date 19401227 legal status the legal status is an assumption and is. The zeolites used in catalytic cracking are chosen to give high percentages of hydrocarbons with between 5 and 10 carbon atoms particularly useful for petrol gasoline. For the love of physics walter lewin may 16, 2011 duration. Catalytic reforming is a chemical process used to convert petroleum. Reforming takes straight chain hydrocarbons in the c 6 to c 8 range from the gasoline or naphtha fractions and rearranges them into compounds containing benzene rings.
Catalytic cracking takes place in a reactor and can convert a majority of heavy hydrocarbons to useful lighter ones. The catalyst is steam stripped to remove any adsorbed hydrocarbons. Petroleum cracking, reforming of hydrocarbon chemical. A petroleum refinery includes many unit operations and unit processes. Hydrogen is produced as a byproduct of the reactions. Cracking is the most important process for the commercial production of gasoline and diesel fuel. During cracking, the long molecules break apart, forming smaller alkanes and alkenes. Cracking, in petroleum refining, the process by which heavy hydrocarbon molecules are broken up into lighter molecules by means of heat and usually pressure. It is the process of braking down the larger, less useful hydrocarbons into smaller, more useful molecules.
I know there are recomended values for the cot but is it possible to calculate. Catalytic reforming an overview sciencedirect topics. Catalytic cracking and catalytic reforming are two processes used in the conversion of crude oil into useful products. Steam hydrocarbon cracking and reforming journal of. Difference between fractional distillation and cracking. Petrol and other fuels are produced from it using fractional distillation. Catalytic cracking is the breakdown of large hydrocarbon compounds into small hydrocarbon molecules with the use of moderate temperatures and pressures in the presence of catalysts. Reforming is a process designed to increase the volume of gasoline that can be produced from a barrel of crude oil.
Thermal reforming alters the properties of lowgrade. Learn complete crude oil refining process from distillation to cracking. This is the first and most basic step in the refining process, and is the precursor to cracking and reforming. Petrol and other fuels are produced from it using fractional distillation and cracking. Process of steam cracking steam cracking is a petrochemical process in which saturated hydrocarbons are broken down into smaller, often unsaturated, hydrocarbons. Fractional distillation and cracking are two such methods. The first stages in the processing of crude oil are described below. Industrial catalytic thermal cracking of hydrocarbon is the process of dissociating or separating higher molecular hydrocarbon to lower hydrocarbon at elevated temperature.
First, crack the vapour of liquid paraffin by passing it over a heated catalyst to produce and collect a mixture of gaseous shortchain hydrocarbons. Since crude oil is a mixture of different components, it should be processed to obtain a better product that has no impurities. Catalytic reforming is a chemical process used to convert petroleum refinery. It is the principal industrial method for producing the lighter alkenes or commonly olefins, including ethene or. Cracking and alkenes crude oil, hydrocarbons and alkanes aqa. Catalytic reforming is the conversion of low octane naphtha into highoctane reformate products. These fractions are obtained from the distillation process as liquids, but are revaporized before cracking. Cracking is a method for obtaining petrol from heavier fractions of crude oil distillation. Select three advantages of cracking from the list below. All but the hydrocracking reaction releases hydrogen which can be used in the.
Oil, and the gases associated with it, consists of a mixture of hundreds of different hydrocarbons. Cracking, in petroleum refining, the process by which heavy hydrocarbon molecules are broken up into lighter molecules by means of heat and usually pressure and sometimes catalysts. In petrochemistry, petroleum geology and organic chemistry, cracking is the process whereby. Thermal you heat large hydrocarbons at high temperatures sometimes high pressures as well until they break apart. Used in the oil and gas industry to refer to a variety of methods whereby a larger product is broken down into smaller byproducts. See how crude oil is converted in useful different fractions and how long chain hydrocarbons are converted in branched.
Catalytic cracking processes have evolved over the years, and are an exemplary display of che. Minimal cracking minimal conversion 10% to 20% typical products suitable for further processing or final blending reforming, catalytic cracking, hydrocracking hydrocracking severe form of hydroprocessing break carbon. Chemical processing how oil refining works howstuffworks. For example, a higher hydrocarbon c 1 0 h 2 2 splits according to the reaction. We examine steam hydrocarbon reforming and steam hydrocarbon cracking as an example of two processes that operate under different chemical reactivity regimes. Hydrocarbon cracking is the process whereby large and heavy hydrocarbon molecules longchain hydrocarbons are broken down up into simpler and smaller bits as light hydrocarbons shortchain hydrocarbons by the breaking a carboncarbon bonds in cracking stock. Hydrocarbons in the naphtha stream have roughly the same number of carbon atoms as those in gasoline, but their structure is generally more complex. A look at the three processes used by the petrochemical industry to get the most from crude oil fractions. Catalytic reforming is a chemical process used to convert. One family of hydrocarbons produced from crude oil is called the alkanes.
Thermal cracking gives mixtures of products containing high proportions of. The hydrocarbon molecules are broken up in a fairly random way to produce mixtures of smaller hydrocarbons, some of. Many industrial chemical processes are taught as distinct contrasting reactions when in fact the unifying comparisons are greater than the contrasts. Petroleum refining crude oil production of materials. Industrial catalytic thermal cracking of hydrocarbon. Catalytic reforming is a chemical process used to convert petroleum refinery naphthas distilled from crude oil typically having low octane ratings into highoctane liquid products called reformates, which are premium blending stocks for highoctane gasoline. The most widely used method of conversion, catalytic cracking is the process of breaking heavy fractions down into lighter ones using a combination of pressure, high heat and a catalyst to quicken the process. Catalytic reforming is a process in which hydrocarbon molecules are structurally rearranged to higher octane forms. The gaseous reaction products flow out of the reactor to the fractionation section of the unit. Catalytic cracking an overview sciencedirect topics. Alkanes alkanes are saturated hydrocarbons contain single.
The purpose of this process is to get the simpler molecules from the complex organized molecules. What are the differences between reforming and cracking in. Petroleum refinery activities start with receipt of. The table shows the octane numbers of some hydrocarbons. Cracking takes place after the process of fractional distillation. Thermal cracking is a process in which hydrocarbons present in crude oil are subject to high heat and temperature to break the molecular bonds and breaking down longchained, higherboiling hydrocarbons into shorterchained, lowerboiling hydrocarbons. The resulting fractions have different uses depending on their properties, and some fractions are more useful than others. The reforming process is a net producer of hydrogen that, if recovered, can be used in hydroprocessing. Compared to thermal cracking, catalytic cracking occurs at lower temperatures and pressures, is more selective and flexible, and incorporates a catalyst. Bp educational service hydrocarbons from crude oil. Model the industrial process of cracking larger hydrocarbons to produce smaller alkanes that can be converted into petrol.
Generally, the rate of cracking and the final products. Learn the basics about the cracking of hydrocarbons and why it is done. Most produce a mixture of saturated and unsaturated hydrocarbons. Catalytic cracking in which a catalyst is employed and which produces high yields of branched and cyclic alkanes. The cracking and reforming of crude oil fractions presentation. The majority of the use we get out of crude oil is as fuel. Cracking is used to convert long alkanes into shorter, more useful hydrocarbons.
It also produces high proportions of branched alkanes and aromatic hydrocarbons like benzene. You can change one fraction into another by one of three methods. Cracking and alkenes crude oil, hydrocarbons and alkanes. Hydrocarbons from oil a2levellevelrevision, chemistry. This process is used to extract usable components, known as fractions, which are released.
We depend largely on crude, the gases associated with it and natural gas mainly methane as the source of liquid fuels petrol, diesel and the feedstock for the chemical industry. Cracking temperature of crude oil refining, hydrocarbons. This lecture explains about cracking of petroleum and its types such as thermal, catalytic and steam cracking and then it discusses about. Main difference catalytic cracking vs catalytic reforming. These are treated in several ways including cracking, isomerisation and reforming. The process of cracking can be conducted on the long chain hydrocarbon. Reforming is generally used to turn smaller straight chain alkanes into branched or cyclic hydrocarbons of the same size. In catalytic cracking, the petroleum or petroleumderived feedstock is fed into a reaction vessel containing a catalyst. It may be performed in three ways, thermal cracking, catalytic cracking and steam cracking. Thermal cracking, also known as pyrolysis, consists of heating the polymer in an inert atmosphere, promoting macromolecules thermal bond scission to a variety of low molecular weight hydrocarbons, i. Cracking reactions take place as the catalyst and hydrocarbons move concurrently downward through the reactor to a zone where the catalyst is separated from the vapors. The major forms of cracking are thermal cracking, catalytic, or cat cracking, steam cracking, and hydrocracking. Difference between catalytic cracking and catalytic reforming.
Useful products from crude oil crude oil is a fossil fuel, formed from the decay of sea creatures over millions of years. There isnt any single unique reaction happening in the cracker. Crude oil cracking reforming and isomerisation youtube. Learn vocabulary, terms, and more with flashcards, games, and other study tools. It is a complex mixture of hydrocarbons, containing mainly alkanes. Making crude oil usefulfractional distillation and cracking. Crude oil is useless until we separate this mixture using fractional distillation. Facts about cracking hydrocarbons present the information about a process of cracking employed in the chemistry and petroleum geology. Cracking and reforming of petroleum how to increase octane. Cracking temperature of crude oil posted in refining, hydrocarbons, oil, and gas. University of zagreb petroleum refining and petrochemical. Cracking involves breaking up heavy molecules into lighter and more valuable hydrocarbons. Catalytic cracking involves taking a heavy oil and heating it to a high temperature in the presence of a catalyst.
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