Investigation of the mechanism reveals the importance of a Co I species that becomes protonated to form Co III -H (i.e. Co III -hydride), to which acetylene inserts via HAT. To improve the durability and recyclability of the homogeneous system, we engineered a heterogeneous version by using a molecular cobaloxime as the linker in a MOF. With the industrial mixture composition, our MOF-based system exhibited the same excellent selectivity (albeit with slightly lower activity) as the homogeneous system, reducing the acetylene concentration to sub-ppm levels with no observed over-hydrogenation within four hours, which represents a ∼20-fold improvement over the two recently reported MOF-based systems. Importantly, our MOF-based system displayed increased longevity and recyclability over the homogeneous system, maintaining catalytic activity for 48 hours over six cycles.