Electron and ion irradiation of zeolites

Three zeolites (analcime, natrolite, and zeolite-Y) were irradiated with 200 and 400 keV electrons. All zeolites amorphized at a relatively low electron fluence. The electron fluences for amorphization by the 200 keV electron irradiation at room temperature were: 7.0 x 10(19) e(-)/cm(2) (analcime), 1.8 x 10(20) e(-)/cm(2) (natrolite), and 3.4 x 10(20) e(-)/cm(2) (zeolite-Y). These doses are equivalent to an energy deposition between 2.6 x 10(10) and 1.27 x 10(11) Gy. An inverse temperature dependence of amorphization dose was observed for all three zeolites, i.e., amorphization dose decreased with increasing temperature. Analcime was also irradiated with 1.5 MeV Kr+ from 300 to 973 K. The amorphization dose by the ion irradiation was constant, similar to 1 x 10(14) ions/cm(2), which is similar to 0.1 dpa of collisional damage and similar to 6.25 x 10(8) Gy of ionizing energy deposition. (C) 2000 Elsevier Science B.V. All rights reserved.