Self-Promoted H2 Formation for Photoinduced Removal of CO to ≤1 ppm in H2 Stream

Photoinduced radical reaction operated at low temperature can be used to remove trace CO in H2 stream by minimizing reverse water-gas-shift. However, H2 consumption resulted from nonselective oxidation by hydroxyl radicals becomes an obstacle to the practical hydrogen stream purification. Inspired by the hydrogen exchange transfer, we demonstrate here that the molecular hydrogen can promote H2 formation from the hydrogen radicals, which generated from the oxidation reaction of CO and H2 with hydroxyl radicals. The slight increment in H2 along with the radical reaction encourages us to configure photocatalytic hydrogen purification fixed bed reactor, which can reduce the CO concentration to ≤1 ppm in the H2 stream.