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Nickel on alumina

The perhydroisoindole system can be prepared by high-pressure hydrogenation of the isoindole over nickel on alumina at elevated temperatures. The use of Raney nickel with dioxane in the reduction of l,3-diphenyl-2-methylisoindole (47) gives the perhydro product (96), accompanied by the isoindoline (97). An alternative route to partially hydrogenated isoindoles has been described in Section III, D. [Pg.137]

The temperature profiles for each catalyst at two different space velocities are plotted in Figure 1. The catalysts with lower nickel content had reasonable activity, but the activity obviously decreased with nickel content. At 25,000/hr space velocity, the 30% nickel-on-alumina catalyst used 50% of the bed to obtain the maximum temperature whereas with 50% nickel the reaction used only 30% or the bed. The method used to prepare the C150-3-02 catalyst resulted in a non-reduceable nickel silicate... [Pg.58]

C150-1-03 50% nickel on alumina and Cl50-4-03 60% nickel on alumina. [Pg.63]

Zhong Z, Yitzhak M, Yuri K, Yanming Z, Aharon G (1999) Sonochemical coating of nanosized nickel on alumina submicrospheres and interaction between the nickel and nickel oxide with substrate. Chem Mater 11 2350-2359... [Pg.267]

That diolefins play a role in benzene formation has also been shown over over a nickel-on-alumina catalyst. Product composition from 1-heptene as a function of the catalyst amount is shown in Fig. 3. This points also to diene intermediates 50). The same was found with carrier-free nickel and platinum 51). [Pg.279]

Cyclohexane dehydrogenates rather rapidly to benzene. Its rearrangement has not been reported over pure metals until now. Cg Ring opening is negligible over platinum and palladium 48, 5i) slight hexane formation was reported over carbon supported rhodium, iridium, and, especially, osmium and ruthenium (702), as well as over nickel on alumina (99). [Pg.306]

Methanation is one of a more general class of Fischer-Tropsch processes in which carbon monoxide and carbon dioxide are hydrogenated to form various light hydrocarbons and water. Although the primary reaction using a nickel on alumina catalyst is the methanation of carbon monoxide, appreciable side reactions can occur in the methanation system. The reactions in the methanation system are shown in Table I and include carbon dioxide... [Pg.116]

HYDROGENATION, CATALYSTS Nickel on alumina. Nickel-Graphite. Palladium-Poly(ethylenimine). Palladium catalysts. Raney nickel. Rhodium catalysts. [Pg.310]

In the field of hydrocarbon conversions, N. D. Zelinskii and his numerous co-workers have published much important information since 1911. Zelinskii s method for the selective dehydrogenation of cyclohexanes over platinum and palladium was first applied to analytical work (155,351,438,439), but in recent years attempts have been made to use it industrially for the manufacture of aromatics from the cyclohexanes contained in petroleum. In addition, nickel on alumina was used for this purpose by V. I. Komarewsky in 1924 (444) and subsequently by N. I. Shuikin (454,455,456). Hydrogen disproportionation of cyclohexenes over platinum or palladium discovered by N. D. Zelinskii (331,387) is a related field of research. Studies of hydrogen disproportionation are being continued, and their application is being extended to compounds such as alkenyl cyclohexanes. The dehydrocyclization of paraffins was reported by this institute (Kazanskil and Plate) simultaneously with B. L. Moldavskil and co-workers and with Karzhev (1937). The catalysts employed by this school have also been tested for the desulfurization of petroleum and shale oil fractions by hydrogenation under atmospheric pressure. Substantial sulfur removal was achieved by the use of platinum and nickel on alumina (392). [Pg.220]

Reaction 1.1 is known as steam reforming. The reaction conditions are fairly severe (>1000°C),and the structural strength of the catalyst is an important point of consideration. The catalyst employed is nickel on alumina, or magnesia, or a mixture of them. Other non-transition metal oxides such as CaO, Si02, and K20 are also added. [Pg.3]

L.M. Knijff, P.H. Bolt, R. van Yperen, A.J. van Dillen, J.W. Geus, Production of nickel-on-alumina catalysts from preshaped bodies K.P. de Jong, Deposition-precipitation onto preshaped carrier bodies — possibilities and limitations P.J. van den Brink, A. Scholten, A. van Wageningen, M.D.A. Lamers, A.J. van Dillen, J.W. Geus, The use of chelating agents for the preparation of iron oxide catalysts for the selective oxidation of hydrogen sulfide, all in Preparation of Catalysts V, Elsevier, Amsterdam, 1991. [Pg.360]

In the case of multiply unsaturated carbonyl compounds, regioselectivity is also sensitive to the nature of the catalyst, to reaction conditions, and to the structure and degree of substitution of the hydrogenated double bonds. For example, hydrogenation of 3,5-heptadien-2-one over nickel on alumina or nickel on zinc oxide occurs mainly at the y,8-double bond. But if the catalyst is modified by the addition of lead or cadmium, reduction occurs mainly at the a,p-double bond (Scheme 24). [Pg.535]

Our preliminary results of nickel on carbon-coated monolithic catalysts show that in a hydrogenation reaction it is five times more active than the corresponding nickel on alumina-washcoated monolithic catalyst without carbon coating. [Pg.605]

An obvious improvement in the steam gasification of biomass for synthesis gas production is to operate at higher temperatures and to use catalysts to gasify as much of the char and liquid products as possible. Laboratory-scale experiments have been carried out to examine this possibility (Mitchell et al, 1980). Nickel precipitated on silica alumina (1 1) and a mixture of silica alumina and nickel on alumina were evaluated as catalysts for steam gasification at 750°C and 850°C and atmospheric pressure. The results are summarized in Table 9.6. The function of the silica alumina is to crack the hydrocarbon... [Pg.295]

Fio. 5. Schematic diagram showing formation of nickel on alumina catalyst. [Pg.104]

Figure 2. Product distribution for cyclohexane conversion to either benzene or hydrogenolysis (>90% n-hexane) products over (a) pure nickel on alumina and (b) the same catalyst after treatment with hexamethyldisilane in H2. Reaction conditions are discussed in references (6) and (8). Figure 2. Product distribution for cyclohexane conversion to either benzene or hydrogenolysis (>90% n-hexane) products over (a) pure nickel on alumina and (b) the same catalyst after treatment with hexamethyldisilane in H2. Reaction conditions are discussed in references (6) and (8).
Natural gas is reacted in a similar manner as gasification of solid hydrocarbons. Methane, the primary component of natural gas, is reacted with steam over a nickel-on-alumina catalyst at 750-800°C to produce synthesis gas (Reaction 9). [Pg.12]

Deactivation of supported nickel on alumina by coke and/or carbon formation is a serious problem in hydrocarbon steam reforming. Several ways have been used to prevent coke and/or carbon deposition. Among them certain additives (e.g. MgG, K2O) which promote... [Pg.245]


See other pages where Nickel on alumina is mentioned: [Pg.14]    [Pg.507]    [Pg.333]    [Pg.46]    [Pg.520]    [Pg.520]    [Pg.75]    [Pg.4]    [Pg.13]    [Pg.229]    [Pg.270]    [Pg.215]    [Pg.283]    [Pg.467]    [Pg.150]    [Pg.426]    [Pg.426]    [Pg.429]    [Pg.430]    [Pg.245]    [Pg.674]    [Pg.681]    [Pg.1411]   
See also in sourсe #XX -- [ Pg.125 ]

See also in sourсe #XX -- [ Pg.7 , Pg.8 ]




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