Temperature swing adsorption process.

摘要

Nitrogen oxides and low molecular weight hydrocarbons are removed from air by subjecting the air to a temperature swing adsorption process using as the adsorbent a composite zeolite product containing both zeolite A and zeolite X. The composite zeolite product is preferably prepared by forming a mixture of an agglomerate of silica and sodium zeolite X having a Si/Al atomic ratio in the range of about 0.9 to less than about 1.2 and a water-soluble sodium aluminate salt; maintaining the mixture at a temperature in the range of about 25 to about 100° C. for a period of time sufficient to convert at least 50% of the silica to sodium zeolite A; and at least partially exchanging the zeolite A-containing product with divalent cations, preferably calcium ions.