Nitrogen adsorption process
AssigneeAir Products and Chemicals, Inc.
InventorsCharles G. Coe, Steven M. Kuznicki
Life of this patent
Estimating the term…
Abstract
The invention relates to a process for adsorption of nitrogen from nitrogen-containing gases using faujasite-containing compositions in which the original hydrogen or monovalent forms are ion exchanged to their polyvalent form and then dehydrated in such a manner as to result in a preponderence of its polyvalent ions in a dehydrated/dehydroxylated state while maintaining substantially the same zeolite content. The resulting compositions, whose cations contained in the faujasitic portion are substantially in their dehydrated/dehydroxylated state, have been found to have surprisingly high selectivities and capacities for the separation of air into nitrogen and oxygen.
Claims10
In a process for the adsorption of nitrogen from nitrogen-containing gases, the improvement which comprises contacting said nitrogen-containing gases with a polyvalent cation exchanged zeolitic adsorbent containing at least 50% by weight faujasite and the faujasite portion thereof having a majority of its exchangeable cations present in the polyvalent cation exchanged form, said adsorbent having been dehydrated in such a manner as to minimize the amount of water in the gaseous environment in contact with said adsorbent during this dehydration step to a partial pressure of water of less than about 0.4 atmospheres at temperatures above 150.degree. up to about 650.degree. C. thereby resulting in a preponderance of its polyvalent ions in a dehydrated/dehydroxylated state.
Dependencies are inferred from the claim text.