FREQUENCY-RESPONSE STUDIES OF CO2 DIFFUSION IN COMMERCIAL 5A POWDERS AND PELLETS

Diffusion of carbon dioxide in 5A zeolites (laboratory-synthesised and commercial powders, pressed and manufactured pellets) has been invest igated using the frequency-response method. Intra- and intercrystallin e diffusion processes can be distinguished and determined from the res ponse spectra generated. Effects of mass and heat transfer resistances on the response spectra have been observed, but could be eliminated b y dispersing a small amount of sample in a plug of glass-wool and carr ying out measurements at relatively high temperatures.