| abstract |
Zeolites exchanged with lithium ions and, optionally, with polyvalent cations arenprepared by ion-exchanging a sodium-containing zeolite, a potassium-containingnzeolite or a sodium- and potassium-containing zeolite with ammonium ions, therebynreplacing the sodium and/or potassium ions with ammonium ions, and then reactingnthe ammonium ion-exchanged zeolite with a water-soluble lithium compound undernconditions which result in the removal of ammonia from the reaction zone. Polyvalentnions, which may be present in the zeolite undergoing ion-exchange, will not bensubstantially replaced by the ammonium or lithium ions. |