The application of nanosized palladium catalysts has gained growing importance over the last few years. Palladiumbased catalytic methods for fine organic synthesis permits the replacement of traditional labor-consuming techniques in multi-step organic syntheses and provides an improvement from the standpoint of cost and environmental impact. The use of activated carbon "Sibunit" as a substrate for catalysts has been fostered by the substrate's high surface area,
chemical inertness both in acidic and basic media, and at the same time by the absence of very strong acidic centers on its surface which could promote undesirable side reactions during the catalytic run. A conversion of alpha-pinene derivatives to commercial biologically active compounds and fragrances as well as sun screens with ultra violet filtering properties, involves a catalytic hydrogenation as a key intermediate step. The aim of the present work is to clarify the factors favoring the dispersion of Pd metal on carbon. The effect of reduction temperature and pretreatment of the carbon surface on metal size during preparation of Pd on "Sibunit" catalysts for selective verbenol conversion was studied. The
electron microscopy method (TEM) was used to show the influence on Pd metal dispersion of carbon surface oxidation by the oxidant H2O2, HNO3. The catalytic activity of Pd/C catalyst samples in verbenol hydrogenation reaction was determined. Kinetic peculiarities of verbenol hydrogenation over the most active catalyst sample were obtained.
Nanosized carbon fibers are of great importance due to its numerous technological applications. One of its disadvantages is low mechanical strength. This problem could be solved by incorporation of carbon fibers into cavities or channels of ceramic monoliths with foam or honeycomb structure. In the present work the experience of preparation of uniform carbon layer consisting from nanosized fibers onto ceramic monoliths with different geometry will be presented. Carbon fibers were produced by catalytic pyrolysis of methane over nanosized metal particles supported over ceramic monolith. Variation of preparation conditions permits to obtain carbon fibers with different density and thickness.
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