Main group catalysis for H 2 purification based on liquid organic hydrogen carriers.

Molecular hydrogen (H 2 ) is one of the most important energy carriers. In the midterm future, a huge amount of H 2 will be produced from a variety of hydrocarbon sources through conversion and removal of contaminants such as CO and CO 2 . However, bypassing these purification processes is desirable, given their energy consumption and environmental impact, which ultimately increases the cost of H 2 . Here, we demonstrate a strategy to separate H 2 from a gaseous mixture of H 2 /CO/CO 2 /CH 4 that can include an excess of CO and CO 2 relative to H 2 and simultaneously store it in N-heterocyclic compounds that act as liquid organic hydrogen carriers (LOHCs), which can be applied to produce H 2 by subsequent dehydrogenation. Our results demonstrate that LOHCs can potentially be used for H 2 purification from CO- and CO 2 -rich crude H 2 in addition to their well-established use in H 2 storage.