AN FT-RAMAN STUDY OF SOLID-STATE ION-EXCHANGE IN ZEOLITES

This work describes the first application of FT-Raman spectroscopy to the investigation of solid-state ion exchange. The contact-induced ion exchange between the following zeolites was examined: Li-exchanged ze olite A (LI-A) and zeolite Y (Na-Y), Li-A and zeolite X (Na-X), Li-A a nd Ca-exchanged zeolite A (Ca-A). The solid-state ion exchange between zeolite Y (Na-Y, NH4-exchanged Y) and metal salts (LiCl and CaCl2) wa s also studied. The results were verified by powder X-ray diffraction. They are also in good agreement with those obtained from other techni ques. The study demonstrates that FT-Raman spectroscopy is a useful to ol for the study of ion exchange of zeolites in the solid-state. (C) 1 998 Elsevier Science B.V. All rights reserved.