Abstract
The adsorption of molecular oxygen at room temperature on the proton form of MFI zeolites with different Si/Al ratios has been investigated by temperature-programmed desorption (TPD). The internal Si-OH defects (silanol groups) in these zeolites are found to serve as O2 adsorption sites. The apparent activation energies (17.5–21.8 kcal-mol-1) of desorption determined from O2 TPD measurements reveal that the extent of interactions between the Si-OH defects and the adsorbed O2 molecules becomes weaker with decreasing Al content in the zeolite.
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Kim, M.H., Kim, S.J., Hong, S.B. et al. Temperature-programmed desorption study of molecular oxygen adsorbed on MFI-type zeolites. Korean J. Chem. Eng. 15, 566–569 (1998). https://doi.org/10.1007/BF02707112
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DOI: https://doi.org/10.1007/BF02707112