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Nickel-hydrogen catalyst system

Moreover, stable liquid systems made up of nanoparticles coated with a surfactant monolayer and dispersed in an apolar medium could be employed to catalyze reactions involving both apolar substrates (solubilized in the bulk solvent) and polar and amphiphilic substrates (preferentially encapsulated within the reversed micelles or located at the surfactant palisade layer) or could be used as antiwear additives for lubricants. For example, monodisperse nickel boride catalysts were prepared in water/CTAB/hexanol microemulsions and used directly as the catalysts of styrene hydrogenation [215]. [Pg.491]

Fischer-Tropsch A process for converting synthesis gas (a mixture of carbon monoxide and hydrogen) to liquid fuels. Modified versions were known as the Synol and Synthol processes. The process is operated under pressure at 200 to 350°C, over a catalyst. Several different catalyst systems have been used at different periods, notably iron-zinc oxide, nickel-thoria on kieselgtihr, cobalt-thoria on kieselgiihr, and cemented iron oxide. The main products are C5-Cn aliphatic hydrocarbons the aromatics content can be varied by varying the process conditions. The basic reaction was discovered in 1923 by F. Fischer and... [Pg.106]

In addition to the successful reductive carbonylation systems utilizing the rhodium or palladium catalysts described above, a nonnoble metal system has been developed (27). When methyl acetate or dimethyl ether was treated with carbon monoxide and hydrogen in the presence of an iodide compound, a trivalent phosphorous or nitrogen promoter, and a nickel-molybdenum or nickel-tungsten catalyst, EDA was formed. The catalytst is generated in the reaction mixture by addition of appropriate metallic complexes, such as 5 1 combination of bis(triphenylphosphine)-nickel dicarbonyl to molybdenum carbonyl. These same catalyst systems have proven effective as a rhodium replacement in methyl acetate carbonylations (28). Though the rates of EDA formation are slower than with the noble metals, the major advantage is the relative inexpense of catalytic materials. Chemistry virtually identical to noble-metal catalysis probably occurs since reaction profiles are very similar by products include acetic anhydride, acetaldehyde, and methane, with ethanol in trace quantities. [Pg.147]

Hydroxymethylfurfural. 2,5-Di(hydroxymethyl)furan can be synthesized from 5-HMF via hydrogenation (Scheme 16). Under a hydrogen pressure of 7 MPa at 140 °C in the presence of platinum or copper catalysts, practically quantitative yields of 2,5-di(hydroxymethyl)furan can be obtained.However, under similar conditions but with palladium or nickel as catalyst, hydrogenation of the ring system occurs so that 2,5-di(hydroxymethyl)-tetrahydrofuran is obtained as the predominant product. [Pg.42]

In conclusion, four catalyst systems, Pd-KOH/silica, Pd-CsOH/silica, Ni-KOH/silica, and Ni-CsOH/silica, have been investigated for the conversion of acetone to MIBK. Systems highly selective to MIBK have been obtained (Pd-CsOH/silica, 100 % at 473 K). Both the metal and the base affected the product distributions. The nickel catalysts were generally less selective, with MIBK being further hydrogenated to MIBC and isophorone becoming a major product at high temperatures. Over Ni-CsOH/silica, a selectivity of around 30% was... [Pg.73]

When one component of a bimetallic alloy is leached out, a finely divided metal powder of high surface area results. One of the oldest of these so-called skeletal metal catalysts is Raney nickel10,11. Nickel boride is a more recently developed hydrogenation catalyst prepared by the reduction of nickel salts with sodium borohydride12-14. Bimetallic catalysts are often used to achieve selective saturation of a double bond in bifunctional unsaturated systems, e.g. in dienes. Amorphous metal alloys, a newly developed class of metal catalysts15,16, have also been applied in the hydrogenation of alkenes and dienes. [Pg.845]

The IFP hydrocracking process features a dual catalyst system the first catalyst is a promoted nickel-molybdenum amorphous catalyst. It acts to remove sulfur and nitrogen and hydrogenate aromatic rings. The second catalyst is a zeolite that finishes the hydrogenation and promotes the hydrocracking reaction. [Pg.374]


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Catalyst system

Hydrogen systems

Hydrogenous systems

Nickel hydrogen

Nickel hydrogenation catalyst

Nickel system

Nickel-hydrogen system

Systemic nickel

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