Low temperature-high temperature two-stage ion exchange of zeolites
Abstract
Abstract A METHOD FOR REDUCING THE ORIGINAL METAL CONTENT OF A CRYSTALLINE ALUMINOSILICATE ZEOLITE TO AN EXCEPTIONALLY LOW LEVEL WHICH COMPRISES THE STEPS OF: (A) CONTACTING SAID CRYSTALLINE ALUMINOSILICATE WITH A SOLUTION OF A CATION OF A METAL SELECTED FROM GROUPS I TO VIII OF THE PERIODIC TABLE, AMMONIUM AND HYDROGEN AT A TEMPERATURE BETWEEN 50*F. AND 215*F. UNDER ATMOSPHERIC PRESSURE; (B) CONTACTING SAID CRYSTALLINE ALUMINOSILICATE WITH A SOLUTION OF A METAL OF GROUPS I TO VIII OF THE PERIODIC TABLE AT A TEMPERATURE BETWEEN 300*F. AND 600*F UNDER SUFFICINET PRESSURE TO MAINTAIN THE SOLUTION IN THE LIQUID PHASE; AND (C) WITHDRAWING A CATION EXCHANGED ZEOLITE HAVING AT LEAST 80 PERCENT OF ITS INITIAL CATIONS EXCHANGED WITH THE CATIONS OF SAID SOLUTIONS.
Inventors
- 👤 Howard S Sherry
- 👤 Albert B Schwartz
Bibliographic Details
Claims Analysis
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