Fabrication of high-flux SAPO-34 membrane on α-Al₂O₃ four-channel hollow fibers for CO₂ capture from CH₄

High-performance SAPO-34 membranes were synthesized on α-Al₂O₃ four-channel hollow fibers (4CHF) for CO₂ capture. Original and nano-size ball-milled seeds were adopted to induce SAPO-34 membranes. The effects of synthesis temperature and synthesis time were investigated. A uniform seed layer could be readily formed on external surface of the support by dip-coating with ball-milled seeds. The ball-milled seeds could accelerate the growth of SAPO-34 membrane due to small particle size and surface lattice defects. With induction of ball-milled seeds, high-quality zeolite membrane could be reproducibly prepared with reduced synthesis time. The separation performances of 4CHF supported SAPO-34 membranes were evaluated for separation of CO₂/CH₄ binary mixture. High separation performance with a CO₂/CH₄ separation selectivity of 160 and CO₂ permeance of 1.18 × 10^-6 mol m^-2 s^-1 Pa^-1 was achieved on a membrane induced with ball-milled seeds at 453 K for 18 h.