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Vanadium trichloride hydrogenation

The conversion of a higher chloride to a lower chloride by hydrogen reduction has been mentioned earlier in connection with the formation of the relatively less volatile ferrous chloride from ferric chloride. This type of reaction is more general and is widely used. Vanadium trichloride can be reduced to the dichloride by hydrogen at temperatures higher than 500 °C ... [Pg.410]

Vanadous Chloride, vanadium trichloride, VC13.—This halide is obtained by the action of hydrogen chloride on finely divided vanadium at 300° to 400° C.,e or by heating vanadium tetrachloride to 140° C. in a current of carbon dioxide, which removes the chlorine formed at the same time. It can be conveniently made also by boiling vanadium oxy-trichloride, VOCl3, vanadium tetrachloride, VC14, or a mixture of both, with sulphur, under reflux. The reactions involved axe 7... [Pg.41]

Anhydrous vanadium trichloride is a crystalline solid of the colonr of peach blossom. It is extremely hygroscopic, deliquescing to a brown liquid. It gives green solutions in alcohol and ether. Density at 18° C., 3-00. The absorption spectrum has been studied.8 On being strongly heated in hydrogen it is reduced to vanadium dichloride, VCla,... [Pg.41]

TETRACHLOROVANADIUM (7632-51-1) Keep away from water (decomposes, producing heat and forming hydrogen chloride, vanadium trichloride, vanadium oxychloride), radiant heat, and flammable materials lithium, chlorine, and trifluoride. Decomposes slowly to vanadium trichloride and chloride. Fumes in moist air open containers in dry, oxygen-free atmosphere or in inert gas, wearing appropriate personal protective equipment. Chill to below 68°F/20°C before opening. Corrosive to metals, especially in the presence of moisture. [Pg.1129]

VANADIUM TRICHLORIDE OXIDE (7727-18-6) Reacts with moisture in air, forming hydrogen chloride fumes. Reacts with water, forming hydrochloric acid. Air contact causes formation of corrosive hydrogen chloride fumes. Reacts violently with many substances, including bases, sodium, potassium. Aqueous solution incompatible with sulfuric acid, alkalis, ammonia, aliphatic amines, alkanolamines, alkylene oxides, amides, epichlorohydrin, organic anhydrides, isocyanates, nitromethane, vinyl acetate. Attacks metals in the presence of moisture. [Pg.1221]

One of the characteristic features of vanadium carbonyl chemistry is the ease of formation of the very stable hexacoordinate [V(CO)g] ion, which, unlike neutral V(CO)6, possesses the inert gas configuration. In two of the three methods for the preparation of vanadium hexacarbonyl from vanadium trichloride the anion [V(CO)6] is initially formed (61, 62, 63). Upon acidification of the [V(CO)6] anion hydrogen is liberated and vanadium hexacarbonyl produced... [Pg.179]

The method adopted for the preparation of vanadium (II) chloride is the reduction of the trichloride by hydrogen at temperatures not exceeding 675°. [Pg.126]

Transition metal catalysts not only increase the reaction rate but may also affect the outcome of the oxidation, especially the stereochemistry of the products. Whereas hydrogen peroxide alone in acetonitrile oxidizes alkenes to epoxides [729], osmic acid catalyzes syn hydroxylation [736], and tungstic acid catalyzes anti hydroxylation [737]. The most frequently used catalysts are titanium trichloride [732], vanadium pentoxide [733,134], sodium vanadate [735], selenium dioxide [725], chromium trioxide [134], ammonium molybdate [736], tungsten trioxide [737], tungstic acid [737],... [Pg.7]

TiCU is produced by the reduction of the tetrachloride with hydrogen or a metal like silver or mercury. When heated in the air it breaks up, giving the volatile tetrachloride and the solid dichloride. TiCl is deli quescent, forms a reddish violet solution with water, and violet crystals, TiCU 6 H20, from a hydrochloric acid solution. An unstable green hydrate of the same composition is formed when an aqueous solution of the trichloride is covered with ether and saturated at 0° with HC1. From the violet form all the chlorine may be removed by AgNO , but this is probably not true of the green modification. The trichlorides of chromium and vanadium likewise are known in two forms. TiCla forms double salts with the chlorides of rubidium and caesium. It is a more powerful reducing agent than stannous chloride and on this account finds extensive application in both qualitative and quantitative analysis. [Pg.146]

See other pages where Vanadium trichloride hydrogenation is mentioned: [Pg.962]    [Pg.57]    [Pg.41]    [Pg.273]    [Pg.68]    [Pg.66]    [Pg.1215]    [Pg.232]    [Pg.991]    [Pg.1071]    [Pg.1220]    [Pg.1221]    [Pg.690]    [Pg.682]    [Pg.730]    [Pg.49]    [Pg.339]    [Pg.669]    [Pg.764]    [Pg.736]    [Pg.728]    [Pg.36]    [Pg.762]    [Pg.682]    [Pg.502]    [Pg.23]    [Pg.124]    [Pg.110]    [Pg.692]    [Pg.502]    [Pg.1239]    [Pg.81]    [Pg.502]    [Pg.489]    [Pg.635]    [Pg.1070]    [Pg.709]    [Pg.711]    [Pg.1069]   


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Vanadium trichloride

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