Integrating tri-mural nanotraps into a microporous metal-organic framework for C2H2/CO2 and C2H2/C2H4 separation

Abstract

Considering the tremendous significance of purification and capture for acetylene (C2H2) in the fields of manufacturing and the petrochemical industry, seeking appropriate materials with prominent performance is a crucial task and also remains an enduring challenge. To pursue this target, we report a robust microporous metal-organic framework (NUM-15) featuring two types of elaborate tri-mural nanotraps, in which fruitful nano-space confinement for accommodating gas molecules and multiple preferential adsorption sites providing multiple specific interactions with C2H2 were supplied to form cooperative effect for efficient separation property. The NUM-15a (activated NUM-15) exhibits high loading for C2H2 (3.5 mmol g−1) over carbon dioxide (CO2) and ethylene (C2H4) at 298 K and 1.0 bar and shows efficient separation performance for binary C2H2/CO2 and C2H2/C2H4 mixtures. The GCMC calculation revealed the crucial role of the multiple interactions in nanotraps for the selective capture of C2H2. Under ambient conditions, dynamic breakthrough experiments revealed that NUM-15a demonstrates the enormous potential for actual industrial gas separation and is expected to be applied to the correlative industrial process. Both experiments and simulation calculations distinctly demonstrated that fabricating tri-mural nanotraps in MOFs is a feasible strategy for efficient C2H2 capture and separation and provided a new route for exploiting high-performance materials for separation and purification technology.