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Hydroxylamines
Hydroxylamine (also known as hydroxyammonia) is an inorganic compound with the chemical formula . The compound exists as hygroscopic colorless crystals.Greenwood and Earnshaw. ''Chemistry of the Elements.'' 2nd Edition. Reed Educational and Professional Publishing Ltd. pp. 431–432. 1997. Hydroxylamine is almost always provided and used as an aqueous solution or more often as one of its salts such as hydroxylammonium sulfate, a water-soluble solid. Hydroxylamine and its salts are consumed almost exclusively to produce Nylon-6. The Redox, oxidation of Ammonia, to hydroxylamine is a step in biological nitrification. History Hydroxylamine was first prepared as hydroxylammonium chloride in 1865 by the German chemist Wilhelm Lossen, Wilhelm Clemens Lossen (1838-1906); he reacted tin and hydrochloric acid in the presence of ethyl nitrate. It was first prepared in pure form in 1891 by the Dutch chemist Cornelis Adriaan Lobry van Troostenburg de Bruyn, Lobry de Bruyn and by the French ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxylamine-O-sulfonic Acid
Hydroxylamine-''O''-sulfonic acid (HOSA) or aminosulfuric acid is the inorganic compound with molecular formula H3NO4S that is formed by the sulfonation of hydroxylamine with oleum. It is a white, water-soluble and hygroscopic, solid, commonly represented by the condensed structural formula H2NOSO3H, though it actually exists as a zwitterion and thus is more accurately represented as +H3NOSO3−. It is used as a reagent for the introduction of amine groups (–NH2), for the conversion of aldehydes into nitriles and alicyclic compound, alicyclic ketones into lactams (cyclic amides), and for the synthesis of variety of nitrogen-containing heterocycles. Preparation According to a laboratory procedure hydroxylamine-''O''-sulfonic acid can be prepared by treating hydroxylamine sulfate with fuming sulfuric acid (oleum). The industrial process is similar. :(NH3OH)2SO4 + 2SO3 → 2H2NOSO3H + H2SO4 The sulfonation of hydroxylamine can also be effected with chlorosulfonic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethylhydroxylamine
Diethylhydroxylamine (DEHA) is an organic compound with the formula (C2H5)2NOH. Strictly, this is ''N'',''N''-diethylhydroxylamine. It has an isomer, ''N'',''O''-diethylhydroxylamine with the formula EtNHOEt. Pure ''N'',''N''-diethylhydroxylamine is a colorless liquid, although it is usually encountered as a colourless-to-yellow solution in water with an amine-like odor. DEHA can be synthesised from a reaction between triethylamine and a peroxide. Applications DEHA is largely used as an oxygen scavenger in water treatment. It is a volatile oxygen scavenger and reacts in a ratio of 2.8/1 DEHA/O2. It is employed in high pressure (>70 bar) boiler systems due to a very low rate of reaction at low temperatures and pressures. Due to its volatility, it acts as an oxygen scavenger throughout the entire boiler system due to steam carryover. DEHA also reacts with ferrous metals to form a passivized film of magnetite throughout the boiler system. The reduction of toxic heavy metal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N,O-Dimethylhydroxylamine
''N'',''O''-Dimethylhydroxylamine is a methylated hydroxylamine used to form so called 'Weinreb amides' for use in the Weinreb ketone synthesis. It is commercially available as its hydrochloride salt. Synthesis It may be prepared by reacting ethyl chloroformate (or similar) with hydroxylamine followed by treatment with a methylating agent such as dimethyl sulfate Dimethyl sulfate (DMS) is a chemical compound with formula (CH3O)2SO2. As the diester of methanol and sulfuric acid, its formula is often written as ( CH3)2 SO4 or Me2SO4, where CH3 or Me is methyl. Me2SO4 is mainly used as a methylating agen .... The N,O-dimethylhydroxylamine is then liberated by acid hydrolysis followed by neutralization. See also * Methoxyamine * N-methylhydroxylamine References {{DEFAULTSORT:Dimethylhydroxylamine, N,O- Hydroxylamines Methyl compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society and professional association in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 49,000 in the world. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing and Shanghai, People' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxylammonium Chloride
Hydroxylammonium chloride is a chemical compound with the formula . It is the hydrochloric acid salt of hydroxylamine (). Hydroxylamine is a biological intermediate in nitrification (biological oxidation of ammonia with oxygen into nitrite) and in anammox (biological oxidation of nitrite and ammonium into dinitrogen gas) which are important in the nitrogen cycle in soil and in wastewater treatment plants. Applications Hydroxylammonium chloride is used in organic synthesis for preparation of oximes and hydroxamic acids from carboxylic acids, N- and O- substituted hydroxylamines, and addition reactions of carbon-carbon double bond. During the acetyl bromide method of extracting lignin from lignocellulosic biomass, hydroxylammonium chloride can be used to remove bromine and polybromide from the solution. In surface treatments, it is used in the preparation of anti-skinning agents, corrosion inhibitors, and cleaner additives. It is also a starting material for pharmaceuticals an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon-6
Nylon 6 or polycaprolactam is a polymer, in particular semicrystalline polyamide. Unlike most other nylons, nylon 6 is not a condensation polymer, but instead is formed by ring-opening polymerization; this makes it a special case in the comparison between condensation and addition polymers. Its competition with nylon 66 and the example it set have also shaped the economics of the synthetic fibre industry. It is sold under numerous trade names including Perlon (Germany), Dederon (former East Germany), Nylatron, Capron, Ultramid, Akulon, Kapron (former Soviet Union and satellite states), Rugopa (Turkey) and Durethan. History Polycaprolactam was developed by Paul Schlack at IG Farben in late 1930s (first synthesized in 1938) to reproduce the properties of Nylon 66 without violating the patent on its production. (Around the same time, Kohei Hoshino at Toray also succeeded in synthesizing nylon 6.) It was marketed as Perlon, and industrial production with a capacity of 3,500 tons per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox
Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. The oxidation and reduction processes occur simultaneously in the chemical reaction. There are two classes of redox reactions: * Electron transfer, Electron-transfer – Only one (usually) electron flows from the atom, ion, or molecule being oxidized to the atom, ion, or molecule that is reduced. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * Atom transfer – An atom transfers from one Substrate (chemistry), substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously, the oxidation state of oxygen decreases as it accepts electrons r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrification
''Nitrification'' is the biological oxidation of ammonia to nitrate via the intermediary nitrite. Nitrification is an important step in the nitrogen cycle in soil. The process of complete nitrification may occur through separate organisms or entirely within one organism, as in comammox bacteria. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an aerobic process performed by small groups of autotrophic bacteria and archaea. Microbiology Ammonia oxidation The process of nitrification begins with the first stage of ammonia oxidation, where ammonia (NH3) or ammonium (NH4+) get converted into nitrite (NO2−). This first stage is sometimes known as nitritation. It is performed by two groups of organisms, ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). Ammonia-Oxidizing Bacteria Ammonia-Oxidizing Bacteria (AOB) are typically Gram-negative bacteria and belong to Betaproteobacteria and Gammaproteob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilhelm Lossen
Wilhelm Clemens Lossen (8 May 1838 in Kreuznach – 29 October 1906 in Aachen) was a German chemist. He was the brother of geologist Karl August Lossen. From 1857 he studied chemistry at the University of Giessen, then continued his education at Göttingen as a pupil of Friedrich Wöhler. After graduation, he worked as an assistant to Karl Weltzien at the polytechnic in Karlsruhe and as an assistant under Wilhelm Heinrich Heintz at the University of Halle. In 1870 he became an associate professor at Heidelberg, then in 1877 accepted a position as professor of chemistry at the University of Königsberg. He is largely known for his work with hydroxylamines; their preparations, properties and derivatives. The eponymous Lossen rearrangement, refers to the decomposition of hydroxamic acids or their derivatives to yield isocyanates. While a student at Göttingen, he conducted research of cocaine with Albert Niemann. After the untimely death of Niemann in 1861, he continued re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aqueous Solution
An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, also known as sodium chloride (NaCl), in water would be represented as . The word ''aqueous'' (which comes from ''aqua'') means pertaining to, related to, similar to, or dissolved in, water. As water is an excellent solvent and is also naturally abundant, it is a ubiquitous solvent in chemistry. Since water is frequently used as the solvent in experiments, the word solution refers to an aqueous solution, unless the solvent is specified. A ''non-aqueous solution'' is a solution in which the solvent is a liquid, but is not water. Characteristics Substances that are ''hydrophobic'' ('water-fearing') do not dissolve well in water, whereas those that are '' hydrophilic'' ('water-friendly') do. An example of a hydrophilic substance is sodium chloride. In an aqueous solution the hydrogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrochloric Acid
Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is a component of the gastric acid in the digestive systems of most animal species, including humans. Hydrochloric acid is an important laboratory reagent and industrial chemical. Etymology Because it was produced from halite, rock salt according to the methods of Johann Rudolph Glauber, hydrochloric acid was historically called by European alchemists ''spirits of salt'' or ''acidum salis'' (salt acid). Both names are still used, especially in other languages, such as , , , , , , , , , , (''ensan''), zh, 盐酸 (''yánsuān''), and (''yeomsan''). Gaseous HCl was called ''marine acid air''. The name ''muriatic acid'' has the same origin (''muriatic'' means "pertaining to brine or salt", hence ''muriate'' means hydrochloride), and this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethyl Nitrate
Ethyl nitrate is the ethyl ester of nitric acid and has the chemical formula . It is a colourless, volatile, explosive, and extremely flammable liquid. It is used in organic synthesis with use as a nitrating agent and as an intermediate in the preparation of some drugs, dyes, and perfumes. Like nitroglycerin, it's a vasodilator. Ethyl nitrate is found in the atmosphere, where it can react with other gases to form smog. The pollutant was originally thought to have been formed mainly by the combustion of fossil fuels. However recent analysis of ocean water samples reveal that in places where cool water rises from the deep, the water is saturated with alkyl nitrates, likely formed by natural processes. History and synthesis Reaction of ethanol with nitric acid was investigated since the Middle Ages, but the fact that it produces mostly ethyl nitrite was not discovered until the 19th century. Eugène Millon was the first to synthesize ethyl nitrate in 1843 by adding urea to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
