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Transalkylation
In organic chemistry, transalkylation is a chemical reaction involving the transfer of an alkyl group from one organic compound to another. The reaction is used for the transfer of Methyl group, methyl and ethyl groups between benzene rings. This is of particular value in the petrochemical industry to manufacture p-xylene, styrene, and other aromatic compounds. Motivation for using transalkylation reactions is based on a difference in production and demand for benzene, toluene, and xylenes. Transalkylation can convert toluene, which is overproduced, into benzene and xylene, which are under-produced. Zeolites are often used as catalysts in transalkylation reactions. Disproportionation Transalkylation, as used by the petrochemical industry, is often used to convert toluene into benzene and xylenes. This is achieved through a disproportionation reaction of toluene in which one toluene molecule transfers its methyl group to another one. The reaction is not selective, and the xylene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Friedel–Crafts Reaction
The Friedel–Crafts reactions are a set of organic reaction, reactions developed by Charles Friedel and James Crafts in 1877 to attach substituents to an Aromatic hydrocarbon, aromatic ring. Friedel–Crafts reactions are of two main types: alkylation reactions and acylation reactions. Both proceed by electrophilic aromatic substitution. Alkylation With alkenes In commercial applications, the alkylating agents are generally alkenes, some of the largest scale reactions practiced in industry. Such alkylations are of major industrial importance, e.g. for the production of ethylbenzene, the precursor to polystyrene, from benzene and ethylene and for the production of cumene from benzene and propene in cumene process: : : Industrial production typically uses solid acids derived from a zeolite as the catalyst. With alkyl halides Friedel–Crafts alkylation involves the alkylation of an aromatic ring. Traditionally, the alkylating agents are alkyl halides. Many alkylating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Xylene
In organic chemistry, xylene or xylol (; IUPAC name: dimethylbenzene) are any of three organic compounds with the formula . They are derived from the substitution of two hydrogen atoms with methyl groups in a benzene ring; which hydrogens are substituted determines which of three structural isomers results. It is a colorless, flammable, slightly greasy liquid of great industrial value. The mixture is referred to as both xylene and, more precisely, xylenes. Mixed xylenes refers to a mixture of the xylenes plus ethylbenzene. The four compounds have identical molecular formulas . Typically the four compounds are produced together by various catalytic reforming and pyrolysis methods. Occurrence and production Xylenes are an important petrochemical produced by catalytic reforming and also by coal carbonisation in the manufacture of coke fuel. They also occur in crude oil in concentrations of about 0.5–1%, depending on the source. Small quantities occur in gasoline and aircra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Toluene
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon with the chemical formula , often abbreviated as , where Ph stands for the phenyl group. It is a colorless, water Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known liv ...-insoluble liquid with the odor associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) attached to a phenyl group by a single bond. As such, its systematic IUPAC nomenclature of organic chemistry, IUPAC name is methylbenzene. Toluene is predominantly used as an industrial feedstock and a solvent. As the solvent in some types of paint thinner, permanent markers, contact cement and certain types of glue, toluene is sometimes used as a recreational inhalant and has the potential of causin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Organic Chemistry
Organic chemistry is a subdiscipline within chemistry involving the science, scientific study of the structure, properties, and reactions of organic compounds and organic matter, organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J.; Greeves, N. and Warren, S. (2012) ''Organic Chemistry''. Oxford University Press. pp. 1–15. . Study of structure determines their structural formula. Study of properties includes Physical property, physical and Chemical property, chemical properties, and evaluation of Reactivity (chemistry), chemical reactivity to understand their behavior. The study of organic reactions includes the organic synthesis, chemical synthesis of natural products, drugs, and polymers, and study of individual organic molecules in the laboratory and via theoretical (in silico) study. The range of chemicals studied chemistry includes hydrocarbons (compounds containing only carbon and hydrogen) as well as compounds based on carbon, but a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Phenol
Phenol (also known as carbolic acid, phenolic acid, or benzenol) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile and can catch fire. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it requires careful handling because it can cause chemical burns. It is acutely toxic and is considered a health hazard. Phenol was first extracted from coal tar, but today is produced on a large scale (about 7 million tonnes a year) from petroleum-derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds, and is a liquid when manufactured. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates, epoxies, explosives such as picric acid, Bakelite, nylon, detergents, herbicides such as phenoxy herbicides, and numerous pharmaceuti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Molecular Sieve
A molecular sieve is a material with pores of uniform size comparable to that of individual molecules, linking the interior of the solid to its exterior. These materials embody the molecular sieve effect, in which molecules larger than the pores are preferentially sieved, allowing for the selective adsorption of specific compounds based on their molecular size. Many kinds of materials exhibit some molecular sieves, but zeolites dominate the field. Zeolites are almost always aluminosilicates, or variants where some or all of the Si or Al centers are replaced by similarly charged elements. Sieving process The diameters of the pores that comprise molecular sieves are similar in size to small molecules. Large molecules cannot enter or be adsorbed, while smaller molecules can. As a mixture of molecules migrates through the stationary bed of porous, semi-solid substance referred to as a sieve (or matrix), the components of the highest molecular weight (which are unable to pass int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
1,3-Diisopropylbenzene
1,3-Diisopropylbenzene is an aromatic hydrocarbon with the formula C6H4(CHMe2)2 (Me = CH3). It is one of three isomeric diisopropylbenzenes. This colorless liquid is prepared by thermal isomerization of 1,4-diisopropylbenzene over a solid acid catalyst. It is the principal industrial precursor to resorcinol via the Hock rearrangement The cumene process (cumene-phenol process, Hock process) is an industrial process for synthesizing phenol and acetone from benzene and propylene. The term stems from cumene (isopropyl benzene), the intermediate material during the process. It w .... References {{DEFAULTSORT:Diisopropylbenzene, 1,3- Alkylbenzenes Isopropyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hock Rearrangement
The cumene process (cumene-phenol process, Hock process) is an industrial process for synthesizing phenol and acetone from benzene and propylene. The term stems from cumene (isopropyl benzene), the intermediate material during the process. It was invented by R. Ūdris and P. Sergeyev in 1942 (USSR), and independently by Heinrich Hock in 1944. This process converts two relatively cheap starting materials, benzene and propylene, into two more valuable ones, phenol and acetone. Other reactants required are oxygen from air and small amounts of a radical initiator. Most of the worldwide production of phenol and acetone is now based on this method. In 2022, nearly 10.8 million tonnes of phenol was produced by the cumene process. In order for this process to be economical, there must also be demand for the acetone by-product as well as the phenol. Steps of the process Cumene is formed in the gas-phase Friedel–Crafts alkylation of benzene by propene. Benzene and propene are compre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Resorcinol
Resorcinol (or resorcin) is a phenolic compound. It is an organic compound with the formula C6H4(OH)2. It is one of three isomeric benzenediols, the 1,3-isomer (or ''meta- (chemistry), meta''-isomer). Resorcinol crystallizes from benzene as colorless needles that are readily soluble in water, alcohol, and ether, but insoluble in chloroform and carbon disulfide. Production Resorcinol is produced in several steps from benzene, starting with dialkylation with propylene to give 1,3-Diisopropylbenzene, 1,3-diisopropylbenzene. Oxidation and Hock rearrangement of this disubstituted arene gives acetone and resorcinol. Resorcinol is a relatively inexpensive chemical. It is produced in only a very few locations around the world (as of 2010 only four commercial plants were known to be operative: in the United States, Germany, China, and Japan), and is the determining factor in the cost of Phenol formaldehyde resin, PRF adhesives. Production in the United States ended in 2017 with the cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
