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MoO3 supported on mesoporous molecular sieves - new catalysts for alkene metathesis and alkyne polymerization
Topka, Pavel ; Čejka, Jiří (vedoucí práce) ; Červený, Libor (oponent) ; Hlubucek, Vratislav (oponent)
Comprehensive Summary of PhD Thesis MoO3 supported on mesoporous molecular sieves - new catalysts for alkene metathesis and alkyne polymerization MoO3 nanesený na mesoporesních molekulových sítech - nové katalyzátory pro metathesi alkenů a polymerizaci alkinů (souhrn disertační práce) Ing. Pavel Topka J. Heyrovský Institute of Physical Chemistry of the ASCR, v. v. i. Department of Physical and Macromolecular Chemistry Faculty of Science, Charles University in Prague Prague, 2008 2 Introduction Modern homogeneous catalysts for metathesis reactions are based on stable carbene complexes especially of Ru, Mo, and W [1]. For large-scale industrial applications, heterogeneous catalysts remain the preferable choice because of low cost, high stability, easy catalyst regeneration and the possibility of easier separation of the catalyst from the reaction mixture. Typical examples are MoO3/SiO2, WO3/SiO2 and Re2O7/Al2O3, without or with cocatalyst (usually tetraalkyltin). Tungsten and molybdenum oxide catalysts require higher reaction temperatures, where side reactions decreasing metathesis selectivity can occur. Only rhenium oxide catalysts exhibit a high activity and selectivity at reaction temperatures below 100 řC. Supported molybdenum oxide catalysts have received much attention because they are widely used in...
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