Effects of proton irradiation in zeolite-Y

摘要

Radiation effects on zeolite-NaY have been investigated by irradiation with a 500 keV H{sup}+ beam. The crystalline-to-amorphous transition occurs at a total dose equivalent to an ionizing energy deposition of3x1010 Gy and a displacement damage level of 0.05 dpa. The ion exchange capacity of the irradiated zeolite-Nay with 10 mN SrCl{sub}2 or 10 mN AgNO{sub}3 solutions varies with the extent of the damage to the crystalline structure. After 25 hours of exchange, the Sr concentration in the amorphous region is nearly zero. This result shows that radiation-induced amorphization can cause a significant loss in ion exchange capacity. The data also suggest that the radiation damage by proton radiation in zeolite-Nay is through both ionizing and displacement processes. The result from Ag-exchange reaction with the irradiated zeolite suggests that higher radiation dose is required to block the penetration of Ag into the supercages. The Ag concentration (～3 at. %) in the hilly damaged region suggests that the cations in the small cages are still exchangeable even when amorphization has been achieved.