Brønsted acidity study of fiberglass materials by H/D-exchange

The kinetics of hydrogen isotopic exchange over fiberglass materials and reference samples (SiO2, H3PO4/SiO2, and HZSM-5) was studied at 500 °C under the dynamic adsorption–desorption equilibrium. The concentrations and H/D-exchange rates of different Brønsted acid sites (BAS) were determined using the numerical modeling of isotope exchange dynamics. The correlation between H/D-exchange rate of reference samples and their acidity determined by FTIR spectroscopy of adsorbed CO was established. Based on this correlation, the strength of BAS in fiberglass materials was shown to be comparable to that of HZSM-5 zeolite.

The kinetics of hydrogen isotopic exchange over fiberglass materials and reference samples (HZSM-5, SiO2, H3PO4/SiO2) was studied under the dynamic adsorption–desorption equilibrium. The numerical modeling of H/D-exchange dynamics provided the number of different Brønsted acid sites (BAS) of fiberglass materials. Besides, for the first time the correlation between H/D-exchange rate and proton affinity scale was established. The strength of BAS in fiberglass materials was shown to be comparable to that of HZSM-5.Figure optionsDownload as PowerPoint slide