Catalytic cracking of petroleum distillates

Catalytic Cracker Bottoms (CCB) which is the heavy residue from the catalytic cracking of petroleum distillate is a common aromatic feedstock used for synthetic carbons and pitch production. CCB, like other heavy aromatic feedstock, is composed of alkyl-substituted polycondensed aromatics with a very wide molecular weight distribution. 

Pitch is a carbonaceous solid that consists primarily of a complex mixture of polycyclic aromatic compounds [14]. Petroleum pitches are residues of crude oil distillation or of catalytic cracking of petroleum distillates. Coal tar pitches are products of the distillation of coal, whereas synthetic pitches are residues of the treatment of other organic substances. Irrespective of origin, all pitch products have complex chemical compositions. 

Dehydrogenation ofTertiary Amylenes. The starting material here is a CB fraction which is cut from catalytic cracking of petroleum. Two of the tertiary amylene isomers, 2-methyl-l-butene and 2-methyl-2-butene, are recovered in high purity by formation of methyl tertiary butyl ether and cracking of this to produce primarily 2-methyl-2-butene. The amylenes are mixed with steam and dehydrogenated over a catalyst. The crude isoprene can be purified by conventional or extractive distillation. 

Together with Professor W. K. Lewis, he researched the fiuidized catalytic cracking of petroleum and with Professor W. H. McAdams revised Principles of Chemical Engineering, and coauthored the revision of Elements of Fractional Distillation with Professor C. S. Robinson. He was a leading authority on distillation, the production of synthetic rubber, and the demineralization of salt water. 

The principal sources of feedstocks in the United States are the decant oils from petroleum refining operations. These are clarified heavy distillates from the catalytic cracking of gas oils. About 95% of U.S. feedstock use is decant oil. Another source of feedstock is ethylene process tars obtained as the heavy byproducts from the production of ethylene by steam cracking of alkanes, naphthas, and gas oils. There is a wide use of these feedstocks in European production. European and Asian operations also use significant quantities of coal tars, creosote oils, and anthracene oils, the distillates from the high temperature coking of coal. European feedstock sources are 50% decant oils and 50% ethylene tars and creosote oils. 

Catalytic cracking of heavy petroleum distillates Catalytic reforming of hydrocarbons to improve octane... 

As well as having roles as supports for metals, silica and alumina are used directly as heterogeneous catalysts. A major application is in the catalytic cracking of heavy petroleum distillates very fine powders of silica and y-alumina possess a huge surface area of 900m g . Large surface areas are a key property of zeolite catalysts (see Section 13.9), the selectivity of which can be tuned by varying the sizes, shapes and Bronsted acidity of their cavities and channels we discuss these properties more fully in Section 26.7. 

Zeolite catalysts are important in the catalytic cracking of heavy petroleum distillates. Their high selectivities and high rates of reactions, coupled with reduced coking effects, are major advantages over the activities of the alumina/silica... 

Practically the only products of petroleum distillation are saturated hydrocarbons. The olefins required by the petrochemical industry are therefore obtained from the individual petroleum fractions by thermal or catalytic cracking. Chain scission and dehydrogenation occur simultaneously during... 

Naphthalene is present, in varying amounts, in all petroleum-derived pyrolysis products which have been exposed to a temperature of over 500 °C or to catalytic processes under relatively severe conditions. It can thus be found in the appropriate distillation fractions of the liquid products of steam cracking for the production of ethylene, in by-products of crude oil cracking and in residues of catalytic gasoline reforming as well as catalytic cracking of gas oils. The extraction of kerosene fractions provides a further source of naphthalene, after the separation of ali-phatics. 

Zeolite catalysts are important in the catalytic cracking of heavy petroleum distillates. Their high selectivities and high... 

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