Catalytic properties of supported Tc in conversion of hydrocarbons, carbon oxides, and hydrazine

Works concerning the use of Tc as a catalyst are reviewed. Catalytic properties of various supported Tc catalysts in dehydrogenation of alcohols and cyclic hydrocarbons, dehydrocyclization of n-hexane and n-heptane, hydrogenation of benzene and carbon oxides, and hydrazine decomposition are examined. The data on the catalytic activity of TcO2 and TcS2 are presented. The nature of active surface of Tc catalysts is treated on the basis of data obtained by various physicochemical methods. The Tc distribution over the support surface, the fixation of Tc on a support, and the effect of the resulting structures on certain catalytic reactions are discussed. A considerable attention is paid to the features of reactions of certain gases (H-2, CO, and CO2) with Tc catalyst surface, which were examined by the chemisorption and temperature-programmed desorption methods. The results obtained are correlated with the data on catalytic hydrogenation of carbon oxides. Also comparison is made of catalytic properties of Tc and its Group VII analogs, Re and Mn. A conclusion is drawn that Tc is a promising catalyst for hydrogenation-dehydrogenation.