Highly durable ZIF-8 tubular membranes via precursor-assisted processing for propylene/propane separation

ZIF-8 membrane has been considered as a potential alternative to the traditional cryogenic distillation process for propylene/propane (C 3 H 6 /C 3 H 8 ) separation. However, the scale-up preparation and stability of ZIF-8 membranes are limited by the weak binding strength between membrane and tubular support. Herein, we report a precursor-assisted processing method that featured strong binding strength at the interface of ZIF-8 membranes and tubular supports. ZIF-8 tubular membranes are then assembled into a membrane module with an effective membrane area of about 157 cm 2 for efficient C 3 H 6 /C 3 H 8 separation. Reliable binding strength is achieved and maintained over 10 min sonication which results in remarkable operation stability over 30 days. The C 3 H 6 permeance and separation factor of this membrane module reached 1.08 × 10 −8 mol m −2 s −1 Pa −1 and 55 at 60 °C and 0.7 MPa, with purity and productivity of 98.3% and 6.2 × 10 −5 mol s −1 , respectively. The good repeatability and durability of the ZIF-8 tubular membrane module demonstrate its potential for further scale-up towards practical application. The module integrated from defects-free tubular ZIF-8 membranes showes efficient and reliable propylene productivity for the binary equimolar propylene/propane mixture separation. • The dense ZIF-8 membranes were prepared by precursor-assisted processing method. • ZIF-8 tubular membranes exhibited high binding strength and reliable stability. • The effective membrane area of assembled module is up to 175 cm 2 . • ZIF-8 membranes module exhibited high propylene purity and productivity.