Investigation of pressure-induced amorphization in hydrated zeolite Li-A and Na-A using synchrotron X-ray diffraction

High pressure synchrotron X-ray diffraction measurements of hydrated zeolit e Li-A and Na-A were carried out at pressures up to 4.1 GPa and at room tem perature in a large volume press. Energy dispersive X-ray diffraction measu rements showed progressive pressure-induced amorphization of both Li-A and Na-A samples. The most rapid loss in long-range ordering occurred at pressu res up to 2.2 GPa followed by a gradual, continued decrease in ordering up to the maximum pressure. At 4.1 GPa the samples appeared to be X-ray amorph ous. After decompression, diffraction patterns at 1 atm indicated that the sample reverted back to their initial crystal structure. (C) 2001 Elsevier Science Ltd. All rights reserved.