Beyond confinement effects in Fischer-Tropsch Co/CNT catalysts

Fischer-Tropsch catalyst preparation parameters, such as cobalt precursor and impregnation solvent, determine structure in fine catalytic performances of Co-based catalysts. Co particles 3–7 nm mean size were prepared by incipient wetness on surface-oxidized CNT. In this work, the crucial impact chemistry operating between support during properties is demonstrated, influence CNT surface characteristics assessed. Very good correlations found between: (i) reduction degree catalysts concentration Co(OOC–) species; (ii) Cohcp/Cofcc ratio amount CO-releasing groups surface; (iii) extent hydrogen spillover quinone groups. The initial activity could only be correlated to a combination features: percentage Cohcp, confinement, spillover, surprisingly inverse particle size. No significant differences SC5+ selectivity observed, accordance with comparable final Finally, stability can Cohcp catalyst. These results confirm precursor/support couple performance Co/CNT catalysts, reveal for first time an correlation activity, which attributed confined phase.