Eelco Vogt - A DNP-supported solid-state NMR study of carbon species in fluid catalytic cracking catalysts

Version 5

      Publication Details (including relevant citation   information):

        Mance, D., Van der Zwan, J., Velthoen, M.E.Z., Meirer, F.,   Weckhuysen, B.M., Baldus, M., Vogt, E.T.C., Chem.   Commun., 53, 3933-3936,   2017

      Abstract:

       

        A combination of solid-state NMR techniques supported by EPR and   SEM-EDX experiments was used to localize different carbon species   (coke) in commercial fluid catalytic cracking catalysts.   Aliphatic coke species formed during the catalytic process and   aromatic coke species deposited directly from the feedstock   respond differently to dynamic nuclear polarization signal   enhancement in integral and crushed FCC particles, indicating   that aromatic species are mostly concentrated on the outside of   the catalyst particles, whereas aliphatic species are also   located on the inside of the FCC particles. The comparison of   solid-state NMR data with and without the DNP radical at low and   ambient temperature suggests the proximity between aromatic   carbon deposits and metals (mostly iron) on the catalyst surface.   These findings potentially indicate that coke and iron deposit   together, or that iron has a role in the formation of aromatic   coke.

      Address (URL): http://dx.doi.org/10.1039/c7cc00849j