RADIOLYTIC HYDROGEN GAS-FORMATION FROM WATER ADSORBED ON TYPE-A ZEOLITES

Gamma-ray irradiation was performed on molecular sieve 3A and 4A zeoli tes adsorbing various amounts of water. The enhancement of hydrogen fo rmation was observed, and the yields of hydrogen gas due to energy tra nsfer from the zeolites to adsorbed water were expressed as a function of p-value, a fraction of adsorbed water, in the same way as formulat ed in the molecular sieve 5A water system. The results obtained in the 4A water system showed good agreement with those in the 5A-water syst em, but the 3A-water system showed definite difference from the others . The present results indicate that anionic framework oxygen atoms of zeolite structure are active sites for energy transfer rather than cat ions contained in zeolite cavities, and that effectiveness of energy t ransfer process depends on the extent of mutual interaction between wa ter molecules, cations and anionic framework oxygen atoms in cation-ex changed type A zeolites.