	US 7,452,407 B2
	Production of carbon monoxide-free hydrogen and helium from a high-purity source
Timothy Christopher Golden, Allentown, Pa. (US); and Thomas Stephen Farris, Bethlehem, Pa. (US)
Assigned to Air Products and Chemicals, Inc., Allentown, Pa. (US)
Filed on Feb. 28, 2006, as Appl. No. 11/365,780.
Prior Publication US 2007/0199446 A1, Aug. 30, 2007
Int. Cl. C01B 3/56 (2006.01); C01B 23/00 (2006.01)

U.S. Cl. 95—97 [95/98; 95/102; 95/140]

36 Claims

14. A process for generating an essentially carbon monoxide-free hydrogen gas stream, the process comprising:

(a) (i) feeding a high-purity hydrogen gas feed stream for around 30 minutes or more through an adsorber that is packed with an adsorbent consisting of a zeolite which is cation exchanged with a metal other than a transition metal and which contains less than about 0.5% by weight of a transition metal, and (ii) recovering an essentially carbon monoxide-free hydrogen gas stream from the adsorber; and

(b) thereafter purging the adsorber by (1) depressurizing it to less than atmospheric pressure, and by (2) (i) recycling a portion of the essentially carbon monoxide-free hydrogen gas stream through the adsorber, and/or (ii) feeding an inert gas stream through the first adsorber.