- Chemical reaction between molecular hydrogen (H2) and another element or a compound, usually in the presence of a catalyst.It may involve adding hydrogen at the sites of double or triple bonds (see bonding) to make them single bonds (i.e., to saturate an unsaturated compound; see saturation), or to aromatic compounds to make them cyclic hydrocarbons. Edible oils with unsaturated fatty acids are liquid at room temperature; food manufacturers use hydrogenation to convert a fraction to saturated fatty acids to make the product more solid. A second type of hydrogenation involves breaking up a compound (hydrogenolysis, or destructive hydrogenation) and is of great importance in the petroleum industry. Numerous processes in gasoline and petrochemical manufacturing are based on it.
* * *chemical reaction between molecular hydrogen and an element or compound, ordinarily in the presence of a catalyst. The reaction may be one in which hydrogen simply adds to a double or triple bond connecting two atoms in the structure of the molecule or one in which the addition of hydrogen results in dissociation (breaking up) of the molecule (called hydrogenolysis, or destructive hydrogenation). Typical hydrogenation reactions include the reaction of hydrogen and nitrogen to form ammonia and the reaction of hydrogen and carbon monoxide to form methanol or hydrocarbons, depending on the choice of catalyst.Nearly all organic compounds containing multiple bonds connecting two atoms can react with hydrogen in the presence of a catalyst. The hydrogenation of organic compounds (through addition and hydrogenolysis) is a reaction of great industrial importance. The addition of hydrogen is used in the production of edible fats from liquid oils. In the petroleum (petroleum refining) industry, numerous processes involved in the manufacture of gasoline and petrochemical products are based on the destructive hydrogenation of hydrocarbons (hydrocarbon). In the late 20th century the production of liquid fuels by hydrogenation of coal (coal mining) has become an attractive alternative to the extraction of petroleum. The industrial importance of the hydrogenation process dates from 1897, when the French chemist Paul Sabatier (Sabatier, Paul) discovered that the introduction of a trace of nickel as a catalyst facilitated the addition of hydrogen to molecules of carbon compounds.The catalysts most commonly used for hydrogenation reactions are the metals nickel, platinum, and palladium and their oxides. For high-pressure hydrogenations, copper chromite and nickel supported on kieselguhr (loose or porous diatomite) are extensively used.
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hydrogénation — [ idrɔʒenasjɔ̃ ] n. f. • 1814; de hydrogéner ♦ Chim., techn. Action d hydrogéner; résultat de cette action. Hydrogénation du charbon : procédé utilisé dans la fabrication d huiles minérales artificielles. ● hydrogénation nom féminin Fixation d… … Encyclopédie Universelle
Hydrogenation — Hy dro*gen*a tion, n. (Chem.) The act of combining with hydrogen, or the state of being so combined. [1913 Webster] … The Collaborative International Dictionary of English
Hydrogénation — Exemple de réaction d hydrogénation: addition de dihydrogène sur l acide maléique pour le transformer en acide succinique, réaction réalisée sous pression (3 atm), catalysée par le palladium. L hydrogénation est une réaction chimique qui… … Wikipédia en Français
Hydrogenation — |date=1996|location=Washington, D.C.|pages=429|id=ISBN 0 8412 3344 6] Because of the importance of hydrogen, many related reactions have been developed for its use. Most hydrogenations use gaseous hydrogen (H2), but some involve the alternative… … Wikipedia
hydrogenation — noun a chemical process that adds hydrogen atoms to an unsaturated oil food producers use hydrogenation to keep fat from becoming rancid • Derivationally related forms: ↑hydrogenate • Hypernyms: ↑chemical process, ↑chemical change, ↑chemical… … Useful english dictionary
hydrogenation — riebalų hidrinimas statusas Aprobuotas sritis pašarai apibrėžtis Aliejaus ir taukų neprisotintųjų glicerolių pakeitimas prisotintaisiais gliceroliais. atitikmenys: angl. hydrogenation vok. Fetthärtung rus. гидрирование; гидрогенизация pranc.… … Lithuanian dictionary (lietuvių žodynas)
hydrogenation — hidrinimas statusas T sritis chemija apibrėžtis Vandenilio prijungimas. atitikmenys: angl. hydrogenation rus. гидрирование; гидрогенизация … Chemijos terminų aiškinamasis žodynas
hydrogenation — noun see hydrogenate … New Collegiate Dictionary
hydrogenation — noun the chemical reaction of hydrogen with another substance, especially with an unsaturated organic compound, and usually under the influence of temperature, pressure and catalysts … Wiktionary
hydrogenation — Addition of hydrogen to a compound, especially to an unsaturated fat or fatty acid; thus, soft fats or oils are solidified or “hardened.” … Medical dictionary