Highly selective separation of small hydrocarbons and carbon dioxide in a metal–organic framework with open copper(ii) coordination sites

Hydrocarbons and carbon dioxide are very important raw materials for industrial products and fine chemicals. The microporous metal–organic framework ZJU-25 with high density of open metal sites, has significantly better separation potential than other MOFs, ZIFs or zeolites. It can fractionate a 5-component CH4/C2H2/C2H4/C2H6/CO2 mixture to yield individual pure components as established by the sorption isotherms and simulated breakthrough and pulse chromatographic experiments. Such separations are likely to have a significant industrial impact, resulting in significant energy savings when compared to current technologies that rely on cryogenic distillation.