Hydrogenation dehydrogenation activity

The carbocation may rearrange, eliminate a proton to produce an olefin, or crack at a beta position to yield an olefin and a new carbocation. Under an atmosphere of hydrogen and in the presence of a catalyst with hydrogenation-dehydrogenation activity, the olefins are hydrogenated to paraffinic compounds. This reaction sequence could be represented as follows ... 

Ruthenium NHC dihydride complex 26 was found to exhibit interesting reversible hydrogenation/dehydrogenation activity (Scheme 10.11) [35,36]. When excess acetone was used as a hydrogen acceptor, dehydrogenation of several alcohols was achieved (Table 10.5). 

High hydrogenation/dehydrogenation activity of the bifunctional catalyst is a prerequisite for pure primary cracking of long chain n-alkanes (4, 19). Thus it is the same type of catalyst that... 

Yields and product properties in hydrocracking are influenced by the relationship between catalyst acidity and the hydrogenation-dehydrogenation activity of the... 

The catalyst is called bifunctional both the carrier and the metallic particles dispersed over the carrier exhibit different catalytic functions. The carrier contains chlorine ions and, as a consequence, it has acid properties and exhibits isomerization and cyclization activities. The metal particles consist of alloys of, for example, Pt/Re which exhibit hydrogenation/dehydrogenation activity. 

Although alumina is widely used as a catalyst support, very few data are available relevant to the catalytic activity of alumina alone for reactions other than dehydration. As Holm and Blue (1) have shown, alumina has appreciable hydrogenation-dehydrogenation activity, especially after drying at high temperatures. The activity was decreased by exposure of the dried catalyst to humid air at room temperature but not by exposure to dry air. 

Liang G, He L, Cheng H, Li W, Li X, Zhang C, et al. The hydrogenation/dehydrogenation activity of supported Ni catalysts and their effect on hexitols selectivity in hydrolytic hydrogenation of cellulose. 

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