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Alkanes catalysts

Alkanes Catalyst (Reaction Time) Intermediates Products Source1... [Pg.48]

Entry hyde alkane Catalyst (h) (°C) Nitroaldols (%) sytv.anti syn (%)... [Pg.222]

Entry Alkane Catalyst TfC) Oxidant/others Conversion (%) Selectivity (%) Products Ref. [Pg.642]

Silver ions form similar aikene complexes which are soluble in aqueous solution and may be used to eifect the separation of unsaturated hydrocarbons from alkanes. Catalysts for the polymerization of alkenes also form metal-alkene complexes which lead to polymerized product. [Pg.334]

Adams catalyst, platinum oxide, Pt02 H20. Produced by fusion of H2PtCl6 with sodium nitrate at 500-550 C and leaching of the cooled melt with water. Stable in air, activated by hydrogen. Used as a hydrogenation catalyst for converting alkenes to alkanes at low pressure and temperature. Often used on Si02... [Pg.15]

An alternative to elucidating the active sites on a surface is to synthesize them. For example, a new catalyst for metathesis of alkanes. [Pg.2706]

Catalytic hydrogenation is mostly used to convert C—C triple bonds into C C double bonds and alkenes into alkanes or to replace allylic or benzylic hetero atoms by hydrogen (H. Kropf, 1980). Simple theory postulates cis- or syn-addition of hydrogen to the C—C triple or double bond with heterogeneous (R. L. Augustine, 1965, 1968, 1976 P. N. Rylander, 1979) and homogeneous (A. J. Birch, 1976) catalysts. Sulfur functions can be removed with reducing metals, e. g. with Raney nickel (G. R. Pettit, 1962 A). Heteroaromatic systems may be reduced with the aid of ruthenium on carbon. [Pg.96]

The uncatalyzed addition of hydrogen to an alkene although exothermic is very slow The rate of hydrogenation increases dramatically however m the presence of cer tain finely divided metal catalysts Platinum is the hydrogenation catalyst most often used although palladium nickel and rhodium are also effective Metal catalyzed addi tion of hydrogen is normally rapid at room temperature and the alkane is produced m high yield usually as the only product... [Pg.231]

Step 4 The second hydrogen atom is transferred forming the alkane The sites on the catalyst surface at which the reaction occurred are free to accept additional hydrogen and alkene molecules... [Pg.232]

Alkenes react with hydrogen in the presence of a platinum palladium rhodium or nickel catalyst to form the corresponding alkane... [Pg.272]

Alkynes are completely hydrogenated yielding alkanes in the presence of the customary metal hydrogenation catalysts... [Pg.384]

Fischer-Tropsch Process. The Hterature on the hydrogenation of carbon monoxide dates back to 1902 when the synthesis of methane from synthesis gas over a nickel catalyst was reported (17). In 1923, F. Fischer and H. Tropsch reported the formation of a mixture of organic compounds they called synthol by reaction of synthesis gas over alkalized iron turnings at 10—15 MPa (99—150 atm) and 400—450°C (18). This mixture contained mostly oxygenated compounds, but also contained a small amount of alkanes and alkenes. Further study of the reaction at 0.7 MPa (6.9 atm) revealed that low pressure favored olefinic and paraffinic hydrocarbons and minimized oxygenates, but at this pressure the reaction rate was very low. Because of their pioneering work on catalytic hydrocarbon synthesis, this class of reactions became known as the Fischer-Tropsch (FT) synthesis. [Pg.164]

Mote stable catalysts ate obtained by using fluorinated graphite or fluorinated alumina as backbones, and Lewis acid halides, such as SbF, TaF, and NbF, which have a relatively low vapor pressure. These Lewis acids ate attached to the fluorinated soHd supports through fluorine bridging. They show high reactivity in Friedel-Crafts type reactions including the isomerization of straight-chain alkanes such as / -hexane. [Pg.565]

Ca.ta.lysts, A small amount of quinoline promotes the formation of rigid foams (qv) from diols and unsaturated dicarboxyhc acids (100). Acrolein and methacrolein 1,4-addition polymerisation is catalysed by lithium complexes of quinoline (101). Organic bases, including quinoline, promote the dehydrogenation of unbranched alkanes to unbranched alkenes using platinum on sodium mordenite (102). The peracetic acid epoxidation of a wide range of alkenes is catalysed by 8-hydroxyquinoline (103). Hydroformylation catalysts have been improved using 2-quinolone [59-31-4] (104) (see Catalysis). [Pg.394]

A catalyst, usually acid, is required to promote chemoselective and regioselective reduction under mild conditions. A variety of organosilanes can be used, but triethylsilane ia the presence of trifiuoroacetic acid is the most frequendy reported. Use of this reagent enables reduction of alkenes to alkanes. Branched alkenes are reduced more readily than unbranched ones. Selective hydrogenation of branched dienes is also possible. [Pg.28]

Alkylation of isobutylene and isobutane in the presence of an acidic catalyst yields isooctane. This reaction proceeds through the same mechanism as dimerization except that during the last step, a proton is transferred from a surrounding alkane instead of one being abstracted by a base. The cation thus formed bonds with the base. Alkylation of aromatics with butylenes is another addition reaction and follows the same general rules with regard to relative rates and product stmcture. Thus 1- and 2-butenes yield j -butyl derivatives and isobutylene yields tert-huty derivatives. [Pg.364]

Catalysts from Physical Mixtures. Two separate catalysts with different functions may be pulverized to fine powders and mixed to form a catalyst system that accomplishes a reaction sequence that neither of the two iadividual catalysts alone can achieve. For such catalyst systems, the reaction products of catalyst A become the feedstocks for catalyst B and vice versa. An example is the three-step isomerization of alkanes by a mixture of... [Pg.195]


See other pages where Alkanes catalysts is mentioned: [Pg.108]    [Pg.87]    [Pg.511]    [Pg.108]    [Pg.1076]    [Pg.108]    [Pg.87]    [Pg.511]    [Pg.108]    [Pg.1076]    [Pg.21]    [Pg.343]    [Pg.2703]    [Pg.102]    [Pg.537]    [Pg.757]    [Pg.236]    [Pg.553]    [Pg.556]    [Pg.556]    [Pg.565]    [Pg.475]    [Pg.466]    [Pg.527]    [Pg.477]    [Pg.467]    [Pg.506]    [Pg.270]    [Pg.477]    [Pg.482]    [Pg.95]    [Pg.152]    [Pg.103]    [Pg.195]    [Pg.201]    [Pg.171]   
See also in sourсe #XX -- [ Pg.558 ]




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Alkane Cracking and Isomerization on Solid Acid Catalysts

Alkane oxidation reactions, mixed metal oxides oxide catalyst

Alkane single-catalyst systems

Alkanes Palladium catalysts

Alkanes cobalt catalysts

Alkanes dehydrogenation catalyst

Alkanes iron catalysts

Alkanes manganese catalysts

Bimetallic catalysts alkane hydrogenolysis

Copper catalysts alkane oxidation

Heterogeneous catalyst alkane isomerization

Hydrogenolysis of Alkanes on Bimetallic Catalysts

Hydrogenolysis of Alkanes on Ruthenium Catalysts

Hydrogenolysis of the Lower Alkanes on Single Metal Catalysts Rates, Kinetics, and Mechanisms

Oxidation of Lower Alkanes Over Oxide Catalysts

Practical Platinum Catalysts for Alkane Functionalization

Ruthenium complex catalysts alkane formation

Vanadium catalysts alkane carboxylation

Vanadium catalysts alkane oxidation

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