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The metal–support interactions of titanium dioxide decorated silicon carbide (β-SiC)-supported cobalt catalyst for Fischer–Tropsch synthesis (FTS) were explored by a combination of energy-filtered transmission electron microscopy (EFTEM), 59Co zero-field nuclear magnetic resonance (59Co NMR), and other conventional characterization techniques. From the 2D elemental maps deduced by 2D EFTEM and 59Co NMR analyses, it can be concluded that the nanoscale introduction of the TiO2 into the β-SiC matrix significantly enhances the formation of small and medium-sized cobalt particles. The results revealed that the proper metal–support interaction between cobalt nanoparticles and TiO2 led to the formation of smaller cobalt particles (<15 nm), which possess a large fraction of surface atoms and, thus, significantly contribute to the great enhancement of conversion and the reaction rate. The cobalt time yield of the catalyst after modification increased to 7.5 × 10–5 molCO gCo –1 s–1 at 230 °C, whereas the C5+ selectivity maintained a high level (>90%). In addition, the adequate meso- and macro-pores of the SiC-based support facilitated intimate contact between the reactants and active sites and also accelerated the evacuation of the intermediate products. It was also worth noting that a superior and stable FTS specific rate of 0.56 gC5+ gcatalyst –1 h–1 together with high C5+ selectivity of 91% were obtained at common industrial content of 30 wt % cobalt.

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in Wiley InterScience (www.interscience.wiley.com).Solid foam matrices have been recently introduced and present a highly permeable porous structure with a high porosity (0.60-0.95), which enables a considerably reduction of the pressure drops along the catalyst bed even with a high specific surface area. It appears today that despite the hydrodynamics of trickle-bed reactors operating with conventional packings (spheres, extrudates, monoliths, etc.) has become largely documented in the recent literature, trickle-bed hydrodynamic behaviour with solid foam packings, on the contrary, largely remains terra incognita. In this context, two phases flows (air-water) in solid foams under cocurrent trickle flow conditions were analyzed in a fixed-bed at ambient conditions. From Residence Time Distribution (RTD) curves, a new set of experimental data based on the hydrodynamics parameters (pressure drop and liquid holdup) of solid foams are presented. A model based on a cubic lattice approach developed in previous work is used to calculate the equivalent diameter for solid foam packings. Finally, through the modified Eo¨tvo¨s number and the relative permeability concept, the two-phase pressure drop and liquid holdup are well estimated. These news results are important parameters for the design of new process in trickle flow conditions with solid foam packing.