CuI-Embedded fiber sorbent with CO selective adsorption for High-Purity H2 recovery

Carbon monoxide (CO) removal techniques are critically important in the context of hydrogen (H2) purification to achieve an economically viable hydrogen value chain. Herein, we develop the new type of structured sorbents, CuI-embedded fiber sorbents, fabricated by incorporating Cu sources into MOF/polymer composite fibers, for selective removal of CO from H2-rich gas. CuI-embedded fiber sorbents show remarkable dynamic adsorption performance, 1.4 - 2.6 times greater dynamic sorption capacities than those of pure MIL-101(Cr)/PVDF fiber, across the range of CO compositions and cyclic stability under the static and/or dynamic adsorption conditions. We also confirm that the form-factor of support can influence to the aggregation effect of infused copper species. Notably, compared to the powder form sorbents, these fiber-form sorbents show enhanced copper dispersion ability, resulting in the ultrahigh Cu utilization degree. The new CuI active sites, identified from the in-situ CO diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis, further elucidate the highly dispersed Cu contents, implying that the formation of active metal sites with different micro-environments. This work highlights the new concepts of the adsorption-based carbon monoxide removal system with potential application for high-purity H2 recovery.