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Cumene
Cumene (isopropylbenzene) is an organic compound that contains a benzene ring with an isopropyl substituent. It is a constituent of crude oil and refined fuels. It is a flammable colorless liquid that has a boiling point of 152 °C. Nearly all the cumene that is produced as a pure compound on an industrial scale is converted to cumene hydroperoxide, which is an intermediate in the synthesis of other industrially important chemicals, primarily phenol and acetone (known as the cumene process). Production Commercial production of cumene is by Friedel–Crafts alkylation of benzene with propylene. Cumene producers account for approximately 20% of the global demand for benzene. The original route for manufacturing of cumene was by alkylation of benzene in the liquid phase using sulfuric acid as a catalyst, but because of the complicated neutralization and recycling steps required, together with corrosion problems, this process has been largely replaced. As an alternative, sol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cumene Hydroperoxide
Cumene hydroperoxide is the organic compound with the formula C6H5CMe2OOH (Me = CH3). An oily liquid, it is classified as an organic hydroperoxide. Products of decomposition of cumene hydroperoxide are methylstyrene, acetophenone, and cumyl alcohol. Its formula is C6H5C(CH3)2OOH. It is produced by treatment of cumene with oxygen, an autoxidation. At temperatures >100 °C, oxygen is passed through liquid cumene: : + O2 → Dicumyl peroxide is a side product. Applications Cumene hydroperoxide is an intermediate in the cumene process for producing phenol and acetone from benzene and propene. :: Cumene hydroperoxide is a free radical initiator for production of acrylates. Cumene hydroperoxide is involved as an organic peroxide in the manufacturing of propylene oxide by the oxidation of propylene. This technology was commercialized by Sumitomo Chemical. The oxidation by cumene hydroperoxide of propylene affords propylene oxide and the byproduct cumyl alcohol. The reaction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cumene Process
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 2003, nearly 7 million tonnes of phenol was produced by the cumene process.Manfred Weber, Markus Weber, Michael Kleine-Boymann "Phenol" in Ullmann's Encyclopedia of Industrial Chemistry 2004, Wiley-VCH. . 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 p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C3-Benzenes
The C3-benzenes are a class of organic aromatic compounds which contain a benzene ring and three other carbon atoms. For the hydrocarbons with no further unsaturation, there are four isomers. The chemical formula for all the saturated isomers is C9H12. There are three trimethylbenzenes, three ethylmetylbenzenes, and two propylbenzene isomers. Petrol (gasoline) can contain 3-4% C3-benzenes. Image:1,2,3-trimethylbenzene 200.svg, 1,2,3-trimethylbenzene or Hemellitene Image:1,2,4-Trimethylbenzene.svg, 1,2,4-Trimethylbenzene or Pseudocumene Image:Mesitylen.svg, 1,3,5-Trimethylbenzene or Mesitylene Image:1,2-Ethylmethylbenzol Structural Formulae V.2.svg, 1,2-Ethylmethylbenzene Image:1,3-Ethylmethylbenzol Structural Formulae V.2.svg, 1,3-Ethylmethylbenzene Image:1,4-Ethylmethylbenzol Structural Formulae V.2.svg, 1,4-Ethylmethylbenzene Image:Cumol.svg, Cumene Image:Isocumene.svg, ''n''-Propylbenzene Image:Trans-Propenylbenzene.svg, ''trans''-Propenylbenzene Image:4-vinyltoluene.svg, 4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenol
Phenol (also called carbolic acid) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it requires careful handling because it can cause chemical burns. Phenol was first extracted from coal tar, but today is produced on a large scale (about 7 billion kg/year) from petroleum-derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates, epoxies, Bakelite, nylon, detergents, herbicides such as phenoxy herbicides, and numerous pharmaceutical drugs. Properties Phenol is an organic compound appreciably soluble in water, with about 84.2 g dissolving in 1000 mL (0.895 M). Homogeneous mixtures of phenol and water at phenol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudocumene
1,2,4-Trimethylbenzene, also known as pseudocumene, is an organic compound with the chemical formula CH(CH). Classified as an aromatic hydrocarbon, it is a flammable colorless liquid with a strong odor. It is nearly insoluble in water but soluble in organic solvents. It occurs naturally in coal tar and petroleum (about 3%). It is one of the three isomers of trimethylbenzene. Production Industrially, it is isolated from the C aromatic hydrocarbon fraction during petroleum distillation. Approximately 40% of this fraction is 1,2,4-trimethylbenzene. It is also generated by methylation of toluene and xylenes and the disproportionation of xylene over aluminosilicate catalysts.Karl Griesbaum, Arno Behr, Dieter Biedenkapp, Heinz-Werner Voges, Dorothea Garbe, Christian Paetz, Gerd Collin, Dieter Mayer, Hartmut Höke "Hydrocarbons" in Ullmann's Encyclopedia of Industrial Chemistry 2002 Wiley-VCH, Weinheim. Uses Pseudocumene is a precursor to mellitic anhydride, from which high performance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzene
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline. It is used primarily as a precursor to the manufacture of chemicals with more complex structure, such as ethylbenzene and cumene, of which billions of kilograms are produced annually. Although benzene is a major industrial chemical, it finds limited use in consumer items because of its toxicity. History Discovery The word "''benzene''" derives from "''gum benzoin''" (benzoin res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propylene
Propylene, also known as propene, is an unsaturated organic compound with the chemical formula CH3CH=CH2. It has one double bond, and is the second simplest member of the alkene class of hydrocarbons. It is a colorless gas with a faint petroleum-like odor. Production Steam cracking The dominant technology for producing propylene is steam cracking. The same technology is applied to ethane to ethylene. These two conversions are the #2 and #1 processes in the chemical industry, as judged by their scale. In this process, propane undergoes dehydrogenation. The by-product is hydrogen: :CH3CH2CH3 → CH3CH=CH2 + H2 The yield of propene is about 85 m%. By-products are usually used as fuel for the propane dehydrogenation reaction. Steam cracking is one of the most energy-intensive industrial processes. The feedstock is naphtha or propane, especially in the Middle East, where there is an abundance of propane from oil/gas operations. Propene can be separated by fractional distilla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autoxidation
Autoxidation (sometimes auto-oxidation) refers to oxidations brought about by reactions with oxygen at normal temperatures, without the intervention of flame or electric spark. The term is usually used to describe the gradual degradation of organic compounds in air at ambient temperatures. Many common phenomena can be attributed to autoxidation, such as food going rancid, the 'drying' of varnishes and paints, and the perishing of rubber. It is also an important concept in both industrial chemistry and biology. Autoxidation is therefore a fairly broad term and can encompass examples of photooxygenation and catalytic oxidation. The common mechanism is a free radical chain reaction, where the addition of oxygen gives rise to hydroperoxides and their associated peroxy radicals (ROO•). Typically, an induction period is seen at the start where there is little activity; this is followed by a gradually accelerating take-up of oxygen, giving an autocatalytic reaction which can only be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkylbenzenes
The alkylbenzenes are derivatives of benzene, in which one or more hydrogen atoms are replaced by alkyl groups of different sizes. They are a subset of the aromatic hydrocarbons. The simplest member is toluene, in which a hydrogen atom of the benzene was replaced by a methyl group In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many .... Literature * Allinger, Cava, de Jongh, Johnson, Lebel, Stevens: ''Organische Chemie'', 1. Auflage, Walter de Gruyter, Berlin 1980, , pp. 367–368, 560–562. * Streitwieser / Heathcock: ''Organische Chemie'', 1. Auflage, Verlag Chemie, Weinheim 1980, , pp. 1051, 1073–1080. * Beyer / Walter: ''Lehrbuch der Organischen Chemie'', 19. Auflage, S. Hirzel Verlag, Stuttgart 1981, , pp. 442–444. * Morrison / Boyd: ''Lehrbuch der Organischen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetone
Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscible with water and serves as an important organic solvent in its own right, in industry, home, and laboratory. About 6.7 million tonnes were produced worldwide in 2010, mainly for use as a solvent and production of methyl methacrylate (and from that PMMA) as well as bisphenol A.Acetone World Petrochemicals report, January 2010Stylianos Sifniades, Alan B. Levy, "Acetone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. It is a common building block in |
Dicumyl Peroxide
Dicumyl peroxide is an organic compound with the formula (Me = CH3). Classified as a dialky peroxide, it is produced on a large scale industrially for use as an initiator for the production of low density polyethylene. Production It is synthesized as a by-product in the autoxidation of cumene, which mainly affords cumene hydroperoxide. Alternatively, it can be produced by the addition of hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%†... to α-methylstyrene. Of the ca. 60,000 ton/y production of dialkyl peroxides, dicumyl peroxide is dominant. Properties Dicumyl peroxide is relatively stable compound owing to the steric protection provided by the several substituents adjacent to the peroxide group. Upon heating, it breaks down by homolysis of the relat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalysis
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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