| 摘要 |
<p>Aqueous solution (I) having a pH above 5 and containing cations of at least one metal and at least one complexing agent for the cations, where the proportion of free metal cations in solution is 0.1-99% of the total metal content of the solution, is new. Independent claims are included for: (1) an ion exchange process comprising contacting an adsorbent material with at least one solution of type (I) to incorporate at least part of the metal cations into the adsorbent by ion exchange; (2) an adsorbent obtainable by the process of (1); (3) zeolite X or A particles ion-exchanged with zinc cations by the process of (1) and also containing lithium and/or calcium cations, and optionally comprising 0.5-30 wt.% of a binder, especially a clay; (4) a process for separating or purifying a gas mixture by adsorption using adsorbent particles as in (2) or (3).</p> |
