NMR relaxation of chloroform adsorbed over alkali-exchanged FAU type zeolites

摘要

We have measured the ~1H and ~(13)C NMR longitudinal relaxation times (T_1) of CHCl_3 and ~(13)CHCl_3, respectively, adsorbed over alkali exchanged zeolites of type FAU. Our results suggest that the mobility of the adsorbed molecules at room temperature depends on the zeolite basicity. Moreover, ~1H to ~(13)C cross polarisation (CP) experiments of the adsorbed chloroform show that the optimum contact time at which the maximum signal intensity is observed depends on the host zeolite.