Process for refining nitrogen trifluoride gas using alkali earth metal exchanged and impregnated zeolite
AssigneeHyosung Corporation
InventorsYong-Chul Park, Woo-Sik Jeong, Kwang-Chul Hyun, Jang-Won Lee, Ik-Hyeon Kwon
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Abstract
Disclosed herein are a process for the refinement of nitrogen trifluoride gas and an adsorbent therefor. A nitrogen trifluoride (NF3) gas including carbon tetrafluoride (CF4) as an impurity is permeated into a bed of zeolite 3A, 4A or 5A which undergoes ion exchange and impregnation with alkali earth metal and is thermally treated at 150 to 600° C. for 0.5 to 100 hours so as to be able to selectively adsorb nitrogen trifluoride onto the bed, followed by the desorption of the nitrogen trifluoride therefrom.
Claims10
A process for refining nitrogen trifluoride gas, comprising:
- introducing a gas mixture of nitrogen trifluoride (NF3) and carbon tetrafluoride (CF4) into a bed of zeolite 3A, 4A or 5A to selectively adsorb nitrogen trifluoride onto the bed, with the carbon tetrafluoride passing through the bed, said zeolite 3A, 4A or 5A being ion-exchanged and impregnated with alkali earth metal;
- and
- recovering the nitrogen trifluoride from the bed.
The process as defined in 1, wherein the alkali earth metal is barium (Ba).
Dependencies are inferred from the claim text.