Claims
- 1. A method of separating a more strongly adsorbable component from one or more less strongly adsorbable components residing in a gaseous mixture comprising contacting the gaseous mixture at elevated pressure with a composition and adsorbing said more strongly adsorbed gas specie on the composition wherein the composition is represented by the formula
- M.sup.n+.sub.(2x+y)/n [Si.sub.(2-x-y) Al.sub.(y) Zn.sub.(x) ]O.sub.4 ;
- wherein
- M is a cation selected from Groups 1, 2, 7, 10, 11, 12 and the f Block elements as defined by the
- Periodic Table of the elements as adopted by IUPAC;
- n is the valence of the selected cation; M;
- x is greater than or equal to 0.02 but less than or equal to 1;
- y is a value greater than or equal to 0.98; and
- 2x+y is greater than or equal to 0.80
- wherein the composition of matter has a FAU structure and zinc resides in tetrahedral positions in the framework of the FAU structure.
- 2. A method of separating a more strongly adsorbable component from one or more less strongly adsorbable components residing in a gaseous mixture comprising the steps of:
- a) contacting the gaseous mixture with a composition at a pressure above ambient and adsorbing the more adsorbable component onto the compositions while allowing the less strongly adsorbable components to be recovered as an unadsorbed product;
- b) terminating contact of the gaseous mixture onto the composition and reducing the pressure on the composition thereby desorbing the more strongly adsorbable component;
- c) repressurizing the composition and
- d) repeating steps a)-c) to provide a continuous process wherein the composition is represented by the formula
- M.sup.n+.sub.(2x+y)/n [Si.sub.(2-x-y) Al.sub.(y) Zn.sub.(x) ]O.sub.4 ;
- wherein
- M is a cation selected from Groups 1, 2, 7, 10, 11, 12 and the f Block elements as defined by the Periodic Table of the elements as adopted by IUPAC;
- n is the valence of the selected cation; M;
- x is greater than or equal to 0.02 but less than or equal to 1;
- y is a value greater than or equal to 0.98; and
- 2x+y is greater than or equal to 0.80
- wherein the composition of matter has a FAU structure and zinc resides in tetrahedral positions in the framework of the FAU structure.
- 3. The method of claim 2 wherein the composition is cation exchanged with lithium cations to replace at least 50% of the exchangeable cations in the composition.
- 4. The method of claim 3 wherein said more strongly adsorbable component is nitrogen and one of the less strongly adsorbable components is oxygen.
- 5. The method of claim 2 wherein the gaseous mixture is air.
- 6. The method of claim 2 wherein the adsorbent is contained in a plurality of parallel connected adsorption vessels and the steps are performed within each vessel so that when at least one vessel is undergoing step a), at least one other vessel is undergoing steps b) and/or c).
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of copending U.S. patent application Ser. No. 08/907,748, filed on Aug. 8, 1997, now U.S. Pat. No. 5,997,841, of James Edward Mac Dougall, Thomas Albert Braymer and Charles Gardner Coe, entitled, "Zincoaluminosilicates of the FAU Structure", the Specification which is incorporated herein and made a part of this application.
US Referenced Citations (11)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0476901 |
Mar 1992 |
EPX |
Non-Patent Literature Citations (2)
Entry |
Cruceanu and Coworkers (A1.1 Cuza lasi, Sect. 1c, 1972 18(2) 223-9) (No Month). |
Crystallization of low-silica faujasite (SiO.sub.2 /Al.sub.2 O.sub.3 .about.2.0)--Gunter H. Kuhl, Zeolites, vol. 7(5), pp. 451-457, Sep. 1987. |
Divisions (1)
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Number |
Date |
Country |
Parent |
907748 |
Aug 1997 |
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