1
Chien C Chao: Process for separating nitrogen from mixtures thereof with less polar substances. UOP, Richard G Miller, August 22, 1989: US04859217 (87 worldwide citation)

The highly lithium exchanged forms of zeolite X, particularly the low silica forms of zeolite X which contain more than ninety equivalent percent lithium cations, have been found to exhibit extraordinary capacities and selectivities for nitrogen adsorption. Such adsorbents are to a surprising degree ...


2
Chao Chien Chung: Process for separating nitrogen from mixtures thereof with less polar substances.. Union Carbide, January 4, 1989: EP0297542-A2 (41 worldwide citation)

The highly lithium exchanged forms of zeolite X, particularly the low silica forms of zeolite X which contain more than ninety equivalent percent lithium cations, have been found to exhibit extraordinary capacities and selectivities for nitrogen adsorption. Such adsorbents are to a surprising degree ...


3
Chao Chien Chung: Procede de separation de lazote present dans un melange gazeux, Process for separating nitrogen from mixtures thereof with less polar substances. Union Carbide Corporation, SIM & MCBURNEY, January 19, 1993: CA1312830

-18- PROCESS FOR SEPARATING NITROGEN FROM MIXTURES THEREOF WITH LESS POLAR SUBSTANCES ABSTRACT The highly lithium exchanged forms ofzeolite X, particularly the low silica forms ofzeolite X which contain more than ninety equivalentpercent lithium cations, have been found to exhibitextraordinary capac ...