MFI-type zeolite membrane on hollow fiber substrate for hydrogen separation

High performance MFI-type zeolite membranes on the outer surface of α-Al₂O₃ hollow fibers were synthesized by secondary growth method using pure silica sol without an organic template. X-ray diffraction was used to characterize the phase structure of both the seed layer and zeolite membrane. The morphologies of the seed layer and zeolite membrane were examined by scanning electron microscopy. The zeolite membrane achieved an extraordinary H₂/CO₂ separation factor of 10 with a high H₂ permeance of 5.56×10⁻⁷ mol m⁻² s⁻¹ Pa⁻¹ at 723 K.