Determination of Si/Al ratios in zeolites by proton inelastic scattering

Proton inelastic scattering has been used to determine the bulk ratio of silicon to aluminum in twelve zeolites. This nuclear reaction analytical technique is nondestructive and provides reliable information in short analysis times for light elements at low concentrations. The 844- and 1014-keV states of aluminum and the 1779-keV state of silicon were excited with 3.4-MeV protons, and the resulting gamma rays were counted with a Ge(Li) detector. The results are compared to those obtained from a larger round-robin series of eight separate analyses using six different analytical techniques. The average deviation of the results from the mean values for each sample in the round-robin series is 3.0%. Only two of the analyses fell outside one standard deviation from the adjusted mean, and both of these are within two standard deviations. (orig.)