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Cobalt-based monolithic and powder catalysts for Fischer-Tropsch synthesis were prepared. The aluminasupported catalysts contained cobalt (18.6 ( 0.9 wt %) and rhenium (1.2 ( 0.1 wt %) as active phases. To ensure the comparability of both catalysts, monolithic and powder catalysts were prepared from the same CoRe/γ-Al 2 O 3 active powder. While the monolith was prepared by dip coating, the slurry for the coating procedure was also used for preparation of the powder catalyst. It could be shown that both catalysts have comparable composition, pore structure, Brunauer-Emmett-Teller (BET) surface area, and active metal surface area. Catalytic measurements with suspended powder catalyst in a stirred tank reactor and monolithic catalyst in a fixed-bed reactor in the slug-flow regime were performed during Fischer-Tropsch synthesis. Higher reaction rates at comparable methane selectivities were obtained with the monolithic catalyst. Estimations show that the advantageous mass-transfer characteristics of the monolithic catalyst in the slug-flow regime are responsible for this reaction rate enhancement.

Monolithic honeycomb reactors are characterized by small parallel channels, which make them an interesting approach to be applied as microstructured reactors. Besides the established manufacturing of ceramic honeycombs, these structures exhibit excellent mass transfer characteristics for multiphase reactions combined with degrees of freedom in the structural design. The potential of monolithic honeycomb reactors operated in the beneficial slug flow regime is evaluated for heterogeneously catalyzed gas‐liquid reactions. Results of the Fischer‐Tropsch synthesis and hydrogenation of glucose to sorbitol were analyzed in order to obtain a more generalized picture of the interaction between mass transfer and reaction in small channels operated in multiphase flow.

stoffen sein, wofür derzeit geeignete Prozesse noch fehlen.Auch ein Wasserstoff-basiertes Energiesystem könnte stark von katalytischen Prozessen abhängen, sei es bei

Supported ionic liquid phase (SILP) catalysts are new materials consisting of an ionic liquid, metal catalyst and a porous support. The catalyst is dissolved in the ionic liquid which itself is dispersed as a thin film on the inorganic support. This application combines both the advantages of homogeneous and heterogeneous catalysis and thus bridges the gap between traditional homogeneous and heterogeneous catalysis [1].Especially continuous, gas-phase reactions are highly suited for this novel and innovative technology.An industrially important example is the water gas shift (WGS) reaction: hydrogen can be generated from synthesis gas. Homogeneous WGS catalysts operate at milder temperatures than commercial heterogeneous systems. Since the hydrogen production via WGS is an exothermic reaction, lower temperatures result in higher equilibrium conversions [2].In this contribution we present investigations of homogeneous metal complexes active in the water gas shift reaction which have been immobilized by the SILP technique. In a first set of experiments known homogeneous systems were screened in batch autoclaves. The most active complexes were immobilized and investigated in a continuous gas phase reactor setup. Kinetic studies include variation of reaction temperature, partial pressures of CO 2 and H 2 O, residence time and catalyst loading.The results indicate that SILP derived WGS catalysts may become a promising alternative to conventional heterogeneous systems.