catalytic cracking
Quick Summary
Catalytic cracking is a crucial process in petroleum refining that breaks down heavy hydrocarbon molecules into lighter ones, primarily to produce gasoline and diesel fuel. Unlike thermal cracking, which uses only heat and pressure, catalytic cracking employs a catalyst to achieve this transformation more efficiently and under less severe conditions.
This process involves using a finely divided solid catalyst, often zeolitic, which promotes the cracking of hydrocarbons through mechanisms like the carbonium ion theory. The catalyst facilitates the weakening of carbon-carbon bonds, resulting in smaller, more valuable molecules. Modern catalytic cracking units, such as fluid catalytic crackers, use a circulating catalyst that is continuously regenerated to maintain its efficiency. The cracked products include not only gasoline but also lighter gases that serve as raw materials for the petrochemical industry.123
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petroleum refiningCatalytic crackingThe use of thermal cracking units to convert gas oils into naphtha dates from before 1920. These units produced small quantities of unstable naphthas and large amounts of by-product coke. While they succeeded in providing a small increase in gasoline yields, it was…
Read MoreThe use of thermal cracking units to convert gas oils into naphtha dates from before 1920. These units produced small quantities of unstable naphthas and large amounts of by-product coke. While they succeeded in providing a small increase in gasoline yields, it was…
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cracking…improved the cracking process with catalysts to obtain a higher-octane product. His process was introduced in 1936 by the Socony-Vacuum Oil Company (later Mobil Oil Corporation) and in 1937 by the Sun Oil Company (later Sunoco, Inc.). Catalytic cracking was itself improved in the 1940s with the use of fluidized…
Read More…improved the cracking process with catalysts to obtain a higher-octane product. His process was introduced in 1936 by the Socony-Vacuum Oil Company (later Mobil Oil Corporation) and in 1937 by the Sun Oil Company (later Sunoco, Inc.). Catalytic cracking was itself improved in the 1940s with the use of fluidized…
Read More- gasoline
…was replaced after 1937 by catalytic cracking, the application of catalysts that facilitate chemical reactions producing more gasoline. Other methods used to improve the quality of gasoline and increase its supply include polymerization, converting gaseous olefins, such as propylene and butylene, into larger molecules in the gasoline range; alkylation, a…
Read More…was replaced after 1937 by catalytic cracking, the application of catalysts that facilitate chemical reactions producing more gasoline. Other methods used to improve the quality of gasoline and increase its supply include polymerization, converting gaseous olefins, such as propylene and butylene, into larger molecules in the gasoline range; alkylation, a…
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petrochemicalThe introduction of catalytic cracking in 1937 and increased supplies of natural gas brought further expansion of the industry.
Read MoreThe introduction of catalytic cracking in 1937 and increased supplies of natural gas brought further expansion of the industry.
Read More- petroleum refiningOlefins
Catalytic cracking is also a valuable source of propylene and butylene, but it does not account for a very significant yield of ethylene, the most important of the petrochemical building blocks. Ethylene is polymerized to produce polyethylene or, in combination with propylene, to produce copolymers…
Read MoreCatalytic cracking is also a valuable source of propylene and butylene, but it does not account for a very significant yield of ethylene, the most important of the petrochemical building blocks. Ethylene is polymerized to produce polyethylene or, in combination with propylene, to produce copolymers…
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