AI Article Synopsis
- The stability of nanosized materials, like small cobalt crystallites, is notably different from that of bulk materials.
- In this study, researchers performed a thermodynamic analysis on the oxidation and re-reduction of these small cobalt crystallites, focusing on their behavior as catalysts in the Fischer-Tropsch synthesis.
- The findings indicate that cobalt crystallites smaller than 4.4 nm are prone to oxidation under typical synthesis conditions (specifically, low water to hydrogen pressure ratios and at a temperature of 493 K).
Article Abstract
The stability of nanosized materials differs significantly from the stability of bulk materials. In this study a thermodynamic analysis on the simultaneous oxidation and re-reduction of small metallic cobalt crystallites in the presence of water and hydrogen as a function of the crystallite diameter was performed as a model for catalyst deactivation in the Fischer-Tropsch synthesis. It is shown that spherical cobalt crystallites with a diameter less than 4.4 nm are likely to be oxidized under realistic Fischer-Tropsch synthesis conditions (p(H)(2)(O)/p(H)(2) < 1.5, T = 493 K).
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