Promoters of hydrogenations

Although previous experience indicates that phosphorus is not essential for these reductions, purification of the product is more difficult with its omission. With iiydrocarbons sensitive to further reduction, phosphorus can have a deleterious effect through promotion of hydrogenation of the desired product. Whether or not phosphorus should be employed in an indi-... 

Promotion of Hydrogen Exchange The radicals derived from the coal molecules by simple thermal homolyses and by molecule-induced homolyses initiate exchange reactions between tetralin-d, and the donors in the reaction system—principally diphenyl-methane and the hydroaromatic compounds in the macerals (2. ... 

The salient features of these reactions are the promotion of hydrogen recombination and the scavenging of oxygen radicals by molecular phosphorus. This in turn will reduce the number of effective flame propagating radical species below the level at which the flame can be sustained.26... 

M. Chai, M. Machida, K. Eguchi and H. Arai, Promotion of Hydrogen Permeation on Metal-Dispersed Alumina Membranes and its Application to a Membrane Reactor for Methane Steam Reforming , Appl. Catal. A, 110 239-50 (1994). 

Chai M., Machida M., Eguchi K. and Arai H., Promotion of hydrogen permeation on metal-dispersed alumina membranes and its application to a membrane reactor for methane steam reforming, Appl. Catal. A 110 239 (1994). 

Mechanism for synergic promotion of hydrogen evolution in the dehydrogenation of organic hydrides such as cyclohexane on bimetallic Pt-M catalysts (M = Rh, Ir, Pd, Re, Mo, etc.). 

Table 78.7 Effective promotion of hydrogen evolution and product selectivity in cyclohexane dehydrogenation on the Ni and Mo2C-based R catalysts...

COADSORPTION OF IONS AT THE INTERFACE AND PROMOTION OF HYDROGEN UPTAKE... 

X-Ray diffraction studies on the (l->3)-j8-D-gIucan, curdlan, from Alcaligenes faecalls have shown the existence of microfibril formation, and a triple helical structure is proposed for the crystalline form of this polysaccharide. The effects of applied hydrostatic pressure on the gel structures of the polysaccharide have been reported. The elasticity decreases initially with increasing pressure attributed to a decrease of free water as solvent, but then increases as the pressure is increased due to the promotion of hydrogen bonding by compression. 

Nickel is a weU-recognized promoter of hydrogen-transfer reactions and hence it is expected that it can be appHed in the reactions under discussion. In accord, acceptor-free dehydrogenation of secondary alcohols by Ni NPs supported on alumina has been reported. Low-coordinated Ni° sites and metal/support interfaces are beheved to play significant roles in the catalytic cycle. 

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