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Methyl Ethyl Ketone
Butanone, also known as methyl ethyl ketone (MEK) or ethyl methyl ketone, is an organic compound with the formula CH3C(O)CH2CH3. This colorless liquid ketone has a sharp, sweet odor reminiscent of acetone. It is produced industrially on a large scale, but occurs in nature only in trace amounts.Wilhelm Neier, Guenter Strehlke "2-Butanone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. It is partially soluble in water, and is commonly used as an industrial solvent. It is an isomer of another solvent, tetrahydrofuran. Production Butanone may be produced by oxidation of 2-butanol. The dehydrogenation of 2-butanol is catalysed by copper, zinc, or bronze: :CH3CH(OH)CH2CH3 → CH3C(O)CH2CH3 + H2 This is used to produce approximately 700 million kilograms yearly. Other syntheses that have been examined but not implemented include Wacker oxidation of 2-butene and oxidation of isobutylbenzene, which is analogous to the industrial production of ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merck Index
''The Merck Index'' is an encyclopedia of chemical substance, chemicals, pharmaceutical drug, drugs and biomolecule, biologicals with over 10,000 monographs on single substances or groups of related chemical compound, compounds published online by the Royal Society of Chemistry. History The first edition of the Merck's Index was published in 1889 by the German chemical company Merck Group, Emanuel Merck and was primarily used as a sales catalog for Merck's growing list of chemicals it sold. The American subsidiary was established two years later and continued to publish it. During World War I the US government seized Merck's US operations and made it a separate American "Merck" company that continued to publish the Merck Index. In 2012 the Merck Index was licensed to the Royal Society of Chemistry. An online version of The Merck Index, including historic records and new updates not in the print edition, is commonly available through research libraries. It also includes an append ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalyst
Catalysis () is the increase in rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by 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. The rate increase occurs because the catalyst allows the reaction to occur by an alternative mechanism which may be much faster than the noncatalyzed mechanism. However the noncatalyzed mechanism does remain possible, so that the total rate (catalyzed plus noncatalyzed) can only increase in the presence of the catalyst and never decrease. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrocellulose
Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and sulfuric acid. One of its first major uses was as guncotton, a replacement for gunpowder as propellant in firearms. It was also used to replace gunpowder as a low-order explosive in mining and other applications. In the form of collodion, it was also a critical component in an early photographic emulsion, the use of which revolutionized photography in the 1860s. In the 20th century, it was adapted to automobile lacquer and adhesives. Production The process uses a mixture of nitric acid and sulfuric acid to convert cellulose into nitrocellulose. The quality of the cellulose is important. Hemicellulose, lignin, pentosans, and mineral salts give inferior nitrocelluloses. In organic chemistry, nitrocellulose is a nitrate ester, not a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellulose Acetate
In biochemistry, cellulose acetate refers to any acetate ester of cellulose, usually cellulose diacetate. It was first prepared in 1865. A bioplastic, cellulose acetate is used as a film base in photography, as a component in some coatings, and as a frame material for eyeglasses; it is also used as a synthetic fiber in the manufacture of Cigarette filter, cigarette filters and Playing card, playing cards. In cellulose acetate film, photographic film, cellulose acetate film replaced nitrate film in the 1950s, being far less flammable and cheaper to produce. Water-soluble cellulose acetate (WSCA) has been used as a Prebiotic (nutrition), dietary fiber (prebiotic), in relation with weight loss and Akkermansia muciniphila. History In 1865, French chemist Paul Schützenberger discovered that cellulose reacts with acetic anhydride to form cellulose acetate. The German chemists Arthur Eichengrün and Theodore Becker invented the first soluble forms of cellulose acetate in 1903. In 190 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resin
A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Common resins include amber, hashish, frankincense, myrrh and the animal-derived resin, shellac. Resins are used in varnishes, adhesives, food additives, incenses and perfumes. Resins protect plants from insects and pathogens, and are secreted in response to injury. Resins repel herbivores, insects, and pathogens, while the volatile natural phenol, phenolic compounds may attract benefactors such as predators of insects that attack the plant. Composition Most plant resins are composed of terpenes. Specific components are alpha-Pinene, alpha-pinene, pinene, beta-pinene, carene, delta-3 carene, and sabinene, the monocyclic terpenes limonene and terpinolene, and smaller amounts of the tricyclic sesquiterpenes, longifolene, caryophyllene, and cad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Gum
Natural gums are polysaccharides of natural origin, capable of causing a large increase in a solution's viscosity, even at small concentrations. They are mostly gum (botany), botanical gums, found in the woody elements of plants or in seed coatings. Human uses Gums are used in the food industry as thickening agents, gelling agents, Emulsion, emulsifying agents, and Food additive#Categories , stabilizers, and in other industrial adhesives, Excipient#Types, binding agents, crystal inhibitors, Brewing#Ingredients, clarifying agents, encapsulating agents, Flocculation , flocculating agents, swelling agents, foam stabilizers, etc. When consumed by humans, many of these gums are fermented by the microbes that inhabit the lower gastrointestinal tract (microbiome) and may influence the ecology and functions of these microscopic communities. Commercial significance Humans have used natural gums for various purposes, including chewing gum , chewing and the manufacturing of a wide rang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naphtha
Naphtha (, recorded as less common or nonstandard in all dictionaries: ) is a flammable liquid hydrocarbon mixture. Generally, it is a fraction of crude oil, but it can also be produced from natural-gas condensates, petroleum distillates, and the fractional distillation of coal tar and peat. In some industries and regions, the name ''naphtha'' refers to crude oil or refined petroleum products such as kerosene or diesel fuel. Naphtha is also known as Shellite in Australia. Etymology The word ''naphtha'' comes from Latin through Ancient Greek (), derived from Middle Persian ''naft'' ("wet", "naphtha"), the latter meaning of which was an assimilation from the Akkadian 𒉌𒆳𒊏 (see Semitic relatives such as Arabic petroleum" Syriac ''naftā'', and Hebrew , meaning petroleum). Antiquity The book of II Maccabees (2nd cent. BC) tells how a "thick water" was put on a sacrifice at the time of Nehemiah and when the sun shone it caught fire. It adds that "those aro ... [...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 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 compr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isobutylbenzene
Isobutylbenzene is a chemical compound with the molecular formula C10H14. It is used in chemical synthesis as a fuel and in pharmaceuticals. For instance, it is used to make pain killers like ibuprofen. Isobutylbenzene is a colorless flammable liquid that is a respiratory irritant. Industrial production is through catalytic carbometalation: toluene adds to propene in the presence of a sodium-potassium catalyst on activated carbon Activated carbon, also called activated charcoal, is a form of carbon commonly used to filter contaminants from water and air, among many other uses. It is processed (activated) to have small, low-volume pores that greatly increase the surface ar ....U.S. Patent #2995610, "Isobutylbenzene Preparation". Assigned August 8, 1961 to Standard Oil Co. References Alkylbenzenes C4-Benzenes {{Hydrocarbons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wacker Oxidation
The Wacker process or the Hoechst-Wacker process (named after the chemical companies of the same name) is an industrial chemical reaction: the aerobic oxidation of ethylene to acetaldehyde in the presence of catalysis, catalytic, aqueous palladium(II) chloride and copper(II) chloride. : The Tsuji-Wacker oxidation refers to a family of reactions inspired by the Wacker process. In Tsuji-Wacker reactions, palladium(II) catalyzes transformation of Α-olefin, α-olefins into carbonyl compounds in various Solvent, solvents. : The development of the Wacker process popularized modern organopalladium chemistry, and Tsuji-Wacker oxidations remain in use today. History The Wacker process was one of the first homogeneous catalysis with organopalladium chemistry applied on an industrial scale. In an 1893 doctoral dissertation on Marcellus natural gas trend, Pennsylvanian natural gas, Francis Clifford Phillips had reported that palladium(II) chloride oxidized ethylene to acetaldehyde, but the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
