Embryonic zeolite-mediated suture synthesis of thin and scalable zeolite membranes for tailored gas separation

Zeolite membranes exhibit considerable potential for gas separation; however, two critical challenges (low permeation flux and scaling-up fabrication) continue to hinder their practical implementation. Here, we propose an embryonic zeolite-mediated suture (EZMS) strategy to synthesize large-area zeolite membranes with stable gas separation performance. The membrane thickness is equivalent to that of the initial seed layer-a feature validated across three distinct zeolite frameworks (STT, CHA, and MFI). For high-silica CHA (also known as SSZ-13) zeolite membranes, the EZMS strategy enables a 5-fold thickness reduction, yielding a CO2 permeance of 1.02 × 10-6 mol·m-2·s-1·Pa-1 (3000 GPU) and a CO2/CH4 selectivity of 158 at 0.2 MPa. Scalability is validated by the successful synthesis of SSZ-13 zeolite membrane bundles with an individual area of 0.5 m2 (40 cm in length). The membranes exhibited excellent high-pressure resistance (>4 MPa) and long-term stability (>220 d) for humid CO2/CH4 separation, representing a high-performance benchmark for biogas upgrading. The reliable synthesis protocol and improved performance highlight the industrial application potential of zeolite membranes.