Benzene from catalytic cracking

The current raw material base for the production of nylon 66 is benzene, which is derived almost entirely from catalytic cracking and reforming of petroleum. Catalytic reduction of benzene to cyclohexane followed by catalyzed air oxidation gives a... 

Ethylene glycol for the synthesis of PET is obfained by air oxidation of ethylene to ethylene oxide (Section 11.8A) followed by hydrolysis to the glycol (Section 11.9A). Ethylene is, in turn, derived entirely from cracking eifher petroleum or ethane derived from natural gas (Section 2.9A). Terephthalic acid is obtained by oxidation of p-xylene, an aromatic hydrocarbon obtained along with benzene and toluene from catalytic cracking and reforming of naphtha and other petroleum fractions (Section 2.9B). 

FEEDSTOCKS. Gaseous or liquid petroleum-derived hydrocarbons or mixture of hydrocarbons from which gasoline, fuel oil. and petrochemicals are produced hy thermal or catalytic cracking. It is also called charging slock. Feedstocks commonly used include ethane, propane, butane, hutene. benzene, loluene. xylene, maphtha, and gas oils. 

From the chemical manufacturing industry, catalytic cracking and catalytic hydrogenation, gas absorption or scrubbing processes in which desired or waste products are removed from a waste stream, the nitration of benzene and toluene where the reactants have limited mutual solubility, and carbonylation processes using carbon monoxide. 

Other interesting products that can be obtained from waste plastics using combined thermal and catalytic processes are alkylaromatic compounds, which possess industrial applications as automatic transmission fluids (ATF), detergents (linear alkyl benzenes, LAB), and improvers of cetane number in diesel fuels [104]. The process uses as raw material the olefins generated in a previous step of thermal and catalytic cracking, which represent a cheaper source of olefins alternative to the currently existing ones. No special details about the conditions applied for the olefin production are indicated, the emphasis being focused on the alkylation step. Alkylation catalysts comprise conventional Lewis... 

Catalytic reactions of hydrocarbons over zeolites are reviewed. The historical development of various mechanistic proposals, particularly of the carbonium ion type, is traced. In spite of numerous catalytic, spectroscopic, and structural studies which have been reported concerning the possible roles of Bronsted acid, Lewis acid, and cationic sites, it still is not possible to formulate a comprehensive mechanistic picture. New activity and product data for cumene cracking and isotope redistribution in deuterated benzenes over Ca-and La-exchanged Y zeolites is presented. Cracking of the isomeric hexanes over alkali metal-exchanged Y and L zeolites has been studied. This cracking is clearly radical rather than carbonium-ion in nature but certain distinct differences from thermal cracking are described. 

Hydeal HOP Toluene, xylenes and other alkyl benzenes heavy reformate, from rerun catalytic reformate, light cycle oil from cat. Cracking A catalytic process for making benzene and naphthalene... 

Desulfurization of petroleum feedstock (FBR), catalytic cracking (MBR or FI BR), hydrodewaxing (FBR), steam reforming of methane or naphtha (FBR), water-gas shift (CO conversion) reaction (FBR-A), ammonia synthesis (FBR-A), methanol from synthesis gas (FBR), oxidation of sulfur dioxide (FBR-A), isomerization of xylenes (FBR-A), catalytic reforming of naphtha (FBR-A), reduction of nitrobenzene to aniline (FBR), butadiene from n-butanes (FBR-A), ethylbenzene by alkylation of benzene (FBR), dehydrogenation of ethylbenzene to styrene (FBR), methyl ethyl ketone from sec-butyl alcohol (by dehydrogenation) (FBR), formaldehyde from methanol (FBR), disproportionation of toluene (FBR-A), dehydration of ethanol (FBR-A), dimethylaniline from aniline and methanol (FBR), vinyl chloride from acetone (FBR), vinyl acetate from acetylene and acetic acid (FBR), phosgene from carbon monoxide (FBR), dichloroethane by oxichlorination of ethylene (FBR), oxidation of ethylene to ethylene oxide (FBR), oxidation of benzene to maleic anhydride (FBR), oxidation of toluene to benzaldehyde (FBR), phthalic anhydride from o-xylene (FBR), furane from butadiene (FBR), acrylonitrile by ammoxidation of propylene (FI BR)... 

Shape selectivity and catalyst deactivation. A serious problem in catalytic cracking and other refinery operations is catalyst deactivation by coking. Coke forms on the catalyst from bulky molecules such as polyalkyl benzenes and polycyclic aromatics that are slow or unable to escape from the catalyst [57], These molecules, in turn are formed mainly from cracked olefins. Coking is severe in zeolites with window-and-supercage structure (chabazite, erionite, Linde A). Zeolites like ZMS-5, with straight channels and no supercages, are much less affected because the formation of bulky coke precursors is sterically inhibited [58]. 

In 1865 just prior to Kekule s synthesis of phenol, Joseph Lister (1827-1912) was experimenting with carbolic acid as an aid to antiseptic surgery which he had pioneered. A mixture of crystallised carbolic acid and shellac (lac plaster) was employed in the finally adopted mode of application. The requirement of phenol for the manufacture of picric acid during the Boer war and other uses resulted in a demand which soon outstripped the resources of phenol/cresols available from coal distillation. Synthetic phenol thus became a potentially important intermediate. The lengthy processing involved in the separation of phenol and the isomeric cresols led to the desirability for specific syntheses. In 1978 of the world production of phenol only 3% came from coal sources by extraction of the mixed phenols (about 1.5% in coal tar) with 10% sodium hydroxide, acidification with carbon dbxide and separation. Phenolic compounds are also formed during catalytic cracking processes in the petroleum industry. There are historically six industriai processes for the production of synthetic phenol, variously from benzene and toluene, some of which are also applicable to the cresols and the dihydric phenols. 

Heavy aromatic solvent naphtha Heavy aromatic solvent naphtha (petroleum) Petroleum distillates, intermediate catalytic cracked (Polyethyl) benzenes Solvent naphtha, heavy aromatic Solvent naphtha (petroleum), heavy aromatic Classification Petroleum hydrocarbon Definition Complex combination of hydrocarbons obtained from distillation of aromatic streams consists of predominantly C9-16 aromatic hydrocarbons... 

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