Preparation And Catalytic Properties Of Carbon Carrier Supported Ruthenium Catalysts

The acetalization or ketalization reaction, a condensation reaction between a carbonyl compound and a diol, is a process that is not only widely used in organic synthesis to protect the carbonyl group of aldehydes and ketones, but also in the synthesis of organic intermediate of paint, make-up, tobacco and pharmaceuticals industry. The products of acetals and ketals in acetalization or ketalization reactions are also important top grade fragrances. Previously, the catalysts used in the acetalization or ketalization reactions are generally protonic acids, Lewis acids, and a number of transitional metal complexes including Rh, Pd, and Pt. In this thesis, the carbon materials supported Ru catalysts were synthesized and been used as efficient catalysts for the acetalization or ketalization reactions.The thesis consists of four chapters as follows:Chapter 1 ReviewsThe following three subsections were reviewed including(1) The noble metal catalyst. The history, classification, and application of the noble metal catalyst were introduced, the Ru-based catalysts were majorly summarized.(2) Carbon materials. The development and application of nano carbon materials were introduced. The catalytic performence and research status for catalytic carrier of carbon nanotube and Vulcan XC-72 were mainly introduced, respectively.(3) Condensation reactions. The main organic condensation reactions and their mechanisms were well introduced.Chapter 2 The catalytic performence of carbon nano-tube supported Ru catalyst(Ru/CNTs)Carbon nano-tube supported Ru catalyst of Ru/CNTs was prepared through impregnating method and characterized by XPS, XRD, BET, TEM and FTIR methods. The result showed that all the Ru NPs are dispersed uniformly on the carbon nano-tube, the larger specific area was obtained after the supporting. The catalytic properties were tested in the condensation of cyclohexanone with 1,2-propandiol in the presence of Ru/CNTs. The influence of the amounts of Ru/CNTs and the cyclohenane(used as solvent), the relative proportion of substrates, the reaction time as well as the temperature were optimized, and the scopes of the substrates were well screened. It was found that the catalyst can be successfully applied to many condensation reaction systems to convert several carbonyl compounds to the corresponding acetals and ketals using ethanediol, 1,2-propandiol, 1,3-propandiol, neopentyl glycol and 2,3-butandiol. The catalyst can be reused at least five times in the reaction between cyclohexanone and 1,2-propandiol without loss of activity.Chapter 3 The catalytic performence of Vulcan XC-72 supported Ru catalyst(Ru/CB)Vulcan XC-72(CB) was simplely treated, and the Vulcan XC-72 supported Ru catalyst of Ru/CB was prepared through impregnating method and characterized by XPS, XRD, BET, TEM and FTIR methods. The result showed that the catalyst has stable structure and large specific area, the active nanoparticles dispersed uniformly on Vulcan XC-72. The catalytic properties were tested in the acetalization and ketalization of carbonyl compounds and diols. It was found that the catalysts can be successfully applied to many condensation reaction systems. High substrate conversions as well as product selectivities were obtained in these condensation reactions. The catalyst can be reused five times in the condensation reaction between cyclohexanone and 1,2-propandiol without loss of activity.