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Cyclododecatriene
Cyclododecatrienes are cyclic trienes with the formula C12H18. Four isomers are known for 1,5,9-cyclododecatriene. The ''trans'',''trans'',''cis''-isomer is a precursor in the production of nylon-12. : Production The ''trans'',''trans'',''cis''-isomer is obtained by cyclotrimerization of butadiene catalyzed by a mixture of titanium tetrachloride and an organoaluminium co-catalyst. Production capacity in 1995 was 8000 tons. : As aforementioned, titanium catalysts predominantly produce the important ''cis'',''trans'',''trans''- isomer. The all-''trans'' isomer is, however, the product from nickel- and chromium-catalyzed trimerization reactions. The yield of cyclododecatriene through these methods is often greater than 80%. The principal side products are the dimer (chemistry), dimers and oligomers of butadiene. Properties All of the isomers of 1,5,9-cyclododecatriene are colorless, possess typical terpene-like odors, and have low melting points. The all-''trans'' isomer melts a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Marl Chemical Park
Marl Chemical Park () is an industrial park in Marl, North Rhine-Westphalia, Germany. It is the third largest industrial cluster in Germany and among the largest chemical industry, chemical production facilities in Europe. The site occupies over 6 square kilometers, hosts 100 chemical plants, employs 10,000 people, and produces 4 million metric tons of chemicals annually. 18 companies are based in the Park, including primary tenant Evonik Industries AG, which also owns and operates the infrastructure through its subsidiary Infracor GmbH. Originally named Chemische Werke Hüls, the complex was built in 1938 by a consortium led by IG Farben to produce polybutadiene, synthetic rubber and other strategic material, war materials for the Third Reich. By 1942 over 5000 workers' families had relocated into new housing which transformed Marl into a company town. At the height of World War II, the Germans also used forced labour under German rule during World War II, slave laborers and pris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Evonik Industries
{{Infobox company , name = Evonik Industries AG , logo = Logo Evonik 2020.svg , image = RellingHaus II, Essen.jpg , image_caption = Evonik's headquarters in Essen, Germany , type = Aktiengesellschaft , traded_as = {{Frankfurt Stock Exchange, EVK MDAX Component , industry = Specialty chemicals , key_people = {{plainlist , * Christian Kullmann {{small, (CEO, Chairman) * Bernd Tönjes (Chairman of the supervisory board) , products = Chemicals , revenue = {{Decrease €15.2 billion (2024){{cite web , url= https://www.evonik.com/en/investor-relations/Reporting.html#tabs-b118b10b7a-item-2d4ab0c2ad-tab , title=Evonik Financial Report 2024 , publisher= Evonik Industries AG , access-date=1 April 2025 , net_income = {{Decrease €222 million (2024) , num_employees = 31,930 (2024) , foundation = {{start date and age, df=yes, 2007 , location = Essen, Germany , homepage = www.evonik.c Evonik Industries AG is a publicly-listed German specialty Chemical substance, chemicals comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Butadiene
1,3-Butadiene () is the organic compound with the formula CH2=CH-CH=CH2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to synthetic rubber. The molecule can be viewed as the union of two vinyl groups. It is the simplest conjugated diene. Although butadiene breaks down quickly in the atmosphere, it is nevertheless found in ambient air in urban and suburban areas as a consequence of its constant emission from motor vehicles. The name butadiene can also refer to the isomer, 1,2-butadiene, which is a cumulated diene with structure H2C=C=CH−CH3. This allene has no industrial significance. History In 1863, French chemist E. Caventou isolated butadiene from the pyrolysis of amyl alcohol. This hydrocarbon was identified as butadiene in 1886, after Henry Edward Armstrong isolated it from among the pyrolysis products of petroleum. In 1910, the Russian chemist Sergei Lebedev polymerized butadiene and obtained a material ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hexabromocyclododecane
Hexabromocyclododecane (HBCD or HBCDD) is a brominated flame retardant. It consists of twelve carbon, eighteen hydrogen, and six bromine atoms tied to the ring. Its primary application is in extruded (XPS) and expanded (EPS) polystyrene foam used as thermal insulation in construction. Other uses are upholstered furniture, automobile interior textiles, car cushions and insulation blocks in trucks, packaging material, video cassette recorder housing, and electric and electronic equipment. According to UNEP, "HBCD is produced in China, Europe, Japan, and the USA. The last known current annual production is approximately 28,000 tonnes per year. The main share of the market volume is used in Europe and China" (figures from 2009 to 2010). Due to its persistent organic pollutant, persistence, toxicity, and ecotoxicity, the Stockholm Convention on Persistent Organic Pollutants decided in May 2013 to list hexabromocyclododecane in Annex A to the convention with specific exemptions for produc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Laurolactam
Laurolactam is an organic compound from the group of macrocyclic lactams. Laurolactam is mainly used as a monomer in engineering plastics, such as nylon-12 and copolyamides.T. Schiffer, G. Oenbrink: ''Cyclododecanol, Cyclododecanone, and Laurolactam.'' In: ''Ullmann's Encyclopedia of Industrial Chemistry.'' Wiley-VCH, Weinheim 2002, . Synthesis Although a derivative of 12-amino dodecanoic acid, it is made from cyclododecatriene. The triene is hydrogenated to the saturated alkane, cyclododecane. For the production of laurolactam, cyclododecane is oxidized with air or oxygen in the presence of boric acid and transition metal salts (e.g. cobalt(II) acetate), obtaining a mixtureH.-J. Arpe: ''Industrielle Organische Chemie.'' 6., vollst. überarb. Aufl., Wiley-VCH Verlag, Weinheim, 2007, . of cyclododecanol and cyclododecanone. This mixture is quantitatively dehydrogenated on a copper contact catalyst to cyclododecanone and this reacted with hydroxylamine to cyclododecanone oxime. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dodecanedioic Acid
Dodecanedioic acid (DDDA) is a dicarboxylic acid with the formula . A white solid, the compound finds a variety of applications ranging from polymers to materials. The unbranched compound is the most commonly encountered C12 dicarboxylic acid. Production DDDA has traditionally been produced from butadiene using a multi-step chemical process. Butadiene is first converted to cyclododecatriene through cyclotrimerization. The triene is then hydrogenated to cyclododecane. Autoxidation by air in the presence of boric acid gives a mixture of cyclodecanol and the cyclododecanone. In the final step, this mixture oxidized to the diacid using nitric acid. An alternative route involves ozonolysis of cyclododecene. : Biological process Paraffin wax can be converted into DDDA on a laboratory scale with a special strain of ''Candida tropicalis'' yeast in a multi-step process. Renewable plant-oil feedstocks sourced from switchgrass could also be used to produce DDDA. Uses DDDA is used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Boric Acid
Boric acid, more specifically orthoboric acid, is a compound of boron, oxygen, and hydrogen with formula . It may also be called hydrogen orthoborate, trihydroxidoboron or boracic acid. It is usually encountered as colorless crystals or a white powder, that dissolves in water, and occurs in nature as the mineral sassolite. It is a weak acid that yields various borate anions and salt (chemistry), salts, and can react with Alcohol (chemistry), alcohols to form borate esters. Boric acid is often used as an antiseptic, insecticide, flame retardant, neutron absorber, or precursor to other boron compounds. The term "boric acid" is also used generically for any oxyacid of boron, such as metaboric acid and tetraboric acid . History Orthoboric acid was first prepared by Wilhelm Homberg (1652–1715) from borax, by the action of mineral acids, and was given the name ("sedative salt of Homberg"). However, boric acid and borates have been used since the time of the ancient Greece, anc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Nylon 12
Nylon 12 is a nylon polymer with the formula CH2)11C(O)NHsub>n. It is made from ω-aminolauric acid or laurolactam monomers that each have 12 carbons, hence the name ‘Nylon 12’. It is one of several nylon polymers. Synthesis Nylon 12 can be produced through two routes. The first being polycondensation of ω-aminolauric acid, a bifunctional monomer with one amine and one carboxylic acid group. n H2N(CH2)11CO2H → CH2)11CONHsub>n + n H2O The second route is ring-opening polymerization of laurolactam at 260–300 °C. Ring opening can be carried out by cationic or anionic initiators, although cationic initiators have not been used commercially due to the product being less stable and oxidized relatively quickly in comparison to those produced by activated anionic polymerization (monomer casting). Ring-opening polymerization is the preferred route for commercial production. :n CH2)11CONH → CH2)11CONHsub>n Properties Nylon 12 exhibits properties between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Beckmann Rearrangement
The Beckmann rearrangement, named after the German chemist Ernst Otto Beckmann (1853–1923), is a rearrangement reaction, rearrangement of an oxime functional group to substituted amides. The rearrangement has also been successfully performed on haloimines and nitrones. Cyclic oximes and haloimines yield lactams. The Beckmann rearrangement is often catalyzed by acid; however, other reagents have been known to promote the rearrangement. These include tosyl chloride, thionyl chloride, phosphorus pentachloride, phosphorus pentoxide, triethylamine, sodium hydroxide, trimethylsilyl iodide among others. The Beckmann fragmentation is another reaction that often competes with the rearrangement, though careful selection of promoting reagent and solvent conditions can favor the formation of one over the other, sometimes giving almost exclusively one product. The rearrangement occurs Stereospecificity, stereospecifically for ketoximes and N-chloro/N-fluoro imines, with the migrating group be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Oxime
In organic chemistry, an oxime is an organic compound belonging to the imines, with the general Chemical formula, formula , where R is an organic Side chain, side-chain and R' may be hydrogen, forming an aldoxime, or another organic functional group, group, forming a ketoxime. O-substituted oximes form a closely related family of compounds. Amidoximes are oximes of amides () with general structure . Oximes are usually generated by the reaction of hydroxylamine with aldehydes () or ketones (). The term ''oxime'' dates back to the 19th century, a combination of the words ''oxygen'' and ''imine''. Structure and properties If the two side-chains on the central carbon are different from each other—either an aldoxime, or a ketoxime with two different "R" groups—the oxime can often have two different geometric stereoisomeric forms according to the E/Z configuration, ''E''/''Z'' configuration. An older terminology of Descriptor (chemistry)#syn, anti, ''syn'' and ''anti'' was used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dehydrogenation
In chemistry, dehydrogenation is a chemical reaction that involves the removal of hydrogen, usually from an organic molecule. It is the reverse of hydrogenation. Dehydrogenation is important, both as a useful reaction and a serious problem. At its simplest, it is a useful way of converting alkanes, which are relatively inert and thus low-valued, to olefins, which are reactive and thus more valuable. Alkenes are precursors to aldehydes (), alcohols (), polymers, and aromatics. As a problematic reaction, the fouling and inactivation of many catalysts arises via coking, which is the dehydrogenative polymerization of organic substrates. Enzymes that catalyze dehydrogenation are called dehydrogenases. In metal manufacturing and repairs, dehydrogenation is a thermal treatment which consists in removing the hydrogen absorbed by an object during an electrochemical or chemical process, performed in a specific oven at a temperature of for a minimum time of 2 hours. Heterogeneous cat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cyclododecanone
Cyclododecanone is an organic compound with the formula (CH2)11CO. It is a cyclic ketone that exists as a white solid at room temperature. Like its smaller analogs but unlike the larger ones, it has a camphor-like odor. History and synthesis It was first obtained by Ružička et al. in 1926 by ketonic decarboxylation. A higher-yield method by acyloin condensation was devised by Prelog et al. in 1947. It is now industrially produced by the oxidation of cyclododecane via cyclododecanol. Uses Cyclododecanone is oxidized on an industrial scale to give the corresponding dicarboxylic acid 1,12- dodecanedioic acid and laurolactam, which are precursors to certain specialized nylons. It is also precursor to cyclohexadecanone Cyclohexadecanone is an organic compound with the formula (CH2)15CO. It is a cyclic ketone, which is a minor component of the musk scent of the civet A civet () is a small, lean, mostly nocturnal mammal native to tropical Asia and Africa, e ..., which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
