| abstract |
The use of a composite zeolitic adsorbent selectively to adsorb nitrous oxide,nethylene, ethane and propane from air that has had water vapour and carbonndioxide removed therefrom, the composite zeolitic adsorbent comprising 5 to 95% bynweight of zeolite A, and 95 to 5% by weight of zeolite X, wherein some or all of thenexchangeable cations of the zeolite A and some or all of the exchangeable cationsnof the zeolite X are divalent cations. The divalent cations are preferably calciumncations. |