Alkanes, dehydrogenation silica-supported

B. D. Chandler, L. 1. Rubinstein, andL. H. Pignolet, Alkane dehydrogenation with silica supported Pt and Pt-Au catalysts derived from phosphine ligated precursors, J. Mol. Catal. A Chem. 133,... 

Figure 4.4 The specific activities of silica-supported ruthenium-copper and osmium-copper catalysts for the dehydrogenation and hydrogenolysis of cyclohexane, the former reaction yielding benzene and the latter alkanes (V. (Reprinted with permission from Academic Press, Inc.)...

Oxidative Dehydrogenation of Ethane. The dehydrogenation of alkanes also occurs, but in a catalytic manner, over molybdenum supported on silica (22,23). In addition to the stoichiometric reactions, the role of the 0 ion in this catalytic reaction is further suggested by the observation that N2O is an effective oxidant at temperatures as low as 280°C, but no reaction is observed at these temperatures with O2 as the oxidant (22). It should be noted that at moderate temperatues N2O gives rise to 0 , whereas O2 yields O2 over Mo/Si02. Under steady-state conditions the rates of formation of C2Hi were in the ratio of 7 1 at 375°C and 3.7 1 at 450°C when N2O and O2 were used as the oxidants, respectively (23). ... 

The synthesis and use of immobilized iridium pincer complexes on solid supports for the transfer dehydrogenation of alkanes have also been examined [131]. Three approaches are reported (i) the post-functionalization of a Mer-rifield resin by incorporating the pincer complex (ii) the covalent bonding of the catalyst to silica via a pendant alkoxysilane linker and (iii) the adsorption of the catalyst onto y-alumina via the interaction of the phenolate group on the para-position of the pincer ligand with the Lewis-acidic sites on the alumina. The last approach showed the best activity, affording thermally robust, recyclable, and active supported ( PCP)Ir (Ir-2) and ( POCOP)Ir (Ir-13) catalysts. 

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