Metal confined in metal-organic framework-based mixed matrix membranes for efficient butadiene recognition separation

The efficient separation of butadiene(1,3-C_(4)H_(6))from C_(4)hydrocarbons is a critical step in petrochemical processes.However,the traditional cryogenic distillation suffers from energy-intensity and serious environmental stress,necessitating the development of alternative technologies for efficient 1,3-C_(4)H_(6)separation.Herein,a 1,3-C_(4)H_(6)recognition mixed matrix membrane is reported via incorporating metal copper encapsulated a metal-organic framework(CuBTC@Cu)into elastic poly(dimethylsiloxane)(PDMS).The resulting CuBTC@Cu/PDMS membrane can efficient separate 1,3-C_(4)H_(6)from various C_(4)hydrocarbons including 1,3-C_(4)H_(6)/n-C_(4)H_(8),1,3-C_(4)H_(6)/iso-C_(4)H_(8),1,3-C_(4)H_(6)/n-C_(4)H_(10)and 1,3-C_(4)H_(6)/iso-C_(4)H_(10),yielding superior selectivity of 5.11,6.35,4.78,and 10.30,respectively,with 1,3-C_(4)H_(6)permeability of 53240 Barrer.Notably,the appropriateπ-complexation interaction between butadiene molecules and CuBTC@Cu as well as suitable transmission channel size enable the membrane only permeable to 1,3-C_(4)H_(6)and block the permeation of other C_(4)hydrocarbons,showing a unique 1,3-C_(4)H_(6)recognition behavior in membrane separation.The concept of affinity-relying separation combining molecular sieving would open a new direction for designing gas membranes for efficient light hydrocarbon separations.