Promoting effect of vanadium on CF2Cl2 destructive sorption over nanocrystalline mesoporous MgO

• CF2Cl2 reaction with mesoporous VOx/MgO is characterized by long induction period.
• Vanadium incorporation promotes the activity of nanocrystalline MgO.
• Mechanism of CF2Cl2 reaction with nanocrystalline VOx/MgO is suggested.
• Formation of surface active sites is supposed to be the rate-determining stage.

The effect of vanadium present in nanocrystalline mesoporous VOx–MgO aerogels on the destructive sorption of difluorodichloromethane was studied using tapered element oscillating microbalance (TEOM), synchronous thermal analyzer (STA) and mass-spectrometric analysis of the gas phase. Vanadium incorporation in the aerogels was found to increase the MgO conversion to MgF2 and shorten the induction period of the solid-state reaction. The mechanisms of the CF2Cl2 reaction with pure and vanadium-modified nanocrystalline MgO aerogels based on the obtained data are analyzed. The obtained results suggest that the formation of nuclei related to the surface active sites is the rate-determining stage of the solid-state reaction.

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