| 摘要 |
<p>PURPOSE:A part of the ion exchange capacity of a novel A type zeolite made by a special method is replaced with calcium or strontium ions and the resultant zeolite is used as an adsorbent to separate oxygen and nitrogen gases from a mixture containing them in high efficiency. CONSTITUTION:(a) An aqueous solution of alkali metal aluminate kept to higher than 10.5 in pH, (b) an aqueous solution of alkali silicate and (c) water adjusted in pH to a specific value previously are prepared respectively so that the molar ratio of a through (c) shows equations in each solution. Then, the water (c) is kept to 60-110 deg.C and the solutions (a) and (b) are added under stirring to the water (c) so as to complete the addition at the same time. Further, stirring of the slurry formed is effected in the same temperature range. Then, the ion exchange capacity of the resultant zeolite is replaced with calcium and/or strontium ions by 0.6-0.95 equivalent. The ion-exchanged zeolite is used as an adsorbent to separate oxygen and nitrogen gases by an adsorption process. As a result, the time required for the operations is remarkably shortened and the amount of the adsorbent to be required is reduced.</p> |
