Metal organic frameworks decorated membrane contactor constructing SO2-philic channels for efficient flue gas desulphurization

Membrane contactor has been considered to be a prospective alternative to traditional technology for toxic acid gases capture. In this study, the mixed matix membrane contactors (MMMCs) with the metal organic frameworks (MOFs, MIL-101(Cr)) as fillers are fabricated for high-efficiency SO 2 removal. The MIL-101(Cr) with microporous structure provides more SO 2 channels for the enhancement of SO 2 absorption flux. Moreover, the open metal sites from MIL-101(Cr) display the high affinity to SO 2 , which construct “SO 2 -philic” channels in the finger-like pore structure , resulting in the increment of SO 2 removal efficiency. The introduction of MIL-101(Cr) into PVDF modifies the physical structure verified by scanning electron microscope (SEM), liquid entry pressure (LEPw) and gas permeation test et al. The newly developed MIL-101(Cr) doped MMMCs exhibit competitive hydrophobicity with the water contact angle of 119°. In particular, the M 9 15 MMMC with MIL-101(Cr) loading 15 wt% displays the optimum SO 2 absorption performance with the SO 2 absorption flux and SO 2 removal efficiency of 1.09 × 10 −3  mol m −2  s −1 and 89.51%, respectively. The SO 2 mass transfer coefficient in membrane ( K m ) is significantly enhanced to 4.44 × 10 −3  m s −1 and membrane phase resistance ( H / K m ) is noticeably decreased to 92.96 s m −1 . Besides, the MIL-101(Cr) doped MMMCs show both the alkali resistance and long-term stability.