Jeong, Yanghwan Kim, Sejin Lee, Minseong Hong, Sungwon Jang, Mun-Gi Choi, Nakwon Hwang, Kyo Seon Baik, Hionsuck Kim, Jin-Kuk Yip, Alex C. K. Choi, Jungkyu 2024-01-19T13:01:22Z 2024-01-19T13:01:22Z 2022-04-05 2022-01 1944-8244 https://pubs.kist.re.kr/handle/201004/115831 Biogas is an environmentally friendly and sustainable energy resource that can substitute or complement conventional fossil fuels. For practical uses, biogas upgrading, mainly through the effective separation of CO2 (0.33 nm) and CH4 (0.38 nm), is required to meet the approximately 90-95% purity of CH4, while CO2 should be concomitantly purified. In this study, a high CO2 perm-selective zeolite membrane was synthesized by heteroepitaxially growing a chabazite (CHA) zeolite seed layer with a synthetic precursor that allowed the formation of all-silica deca-dodecasil 3 rhombohedral (DDR) zeolite (with a pore size of 0.36 x 0.44 nm2). The resulting hydrophobic DDR@CHA hybrid membrane on an asymmetric alpha-Al2O3 tube was thin (ca. 2 mu m) and continuous, thus providing both high flux and permselectivity for CO2 irrespective of the presence or absence of water vapor (the third largest component in the biogas streams). To the best of our knowledge, the CO2 permeance of (2.9 +/- 0.3) x 10-7 mol m-2 s-1 Pa-1 and CO2/CH4 separation factor of ca. 274 +/- 73 at a saturated water vapor partial pressure of ca. 12 kPa at 50 degrees C have the highest CO2/ CH4 separation performance yet achieved. Furthermore, we explored the membrane module properties of the hybrid membrane in terms of the recovery and purity of both CO2 and CH4 under dry and wet conditions. Despite the high intrinsic membrane properties of the current hybrid membrane, reflected by the high permeance and SF, the corresponding module properties indicated that high-performance separation of CO2 and CH4 for the desired biogas upgrading was achieved at a limited processing capacity. This supports the importance of understanding the correlation between the membrane and module properties, as this will provide guidance for the optimal operating conditions. English American Chemical Society p A Hybrid Zeolite Membrane-Based Breakthrough for Simultaneous CO2 Capture and CH4 Upgrading from Biogas Article 10.1021/acsami.1c21277 1 ACS Applied Materials & Interfaces, v.14, no.2, pp.2893 - 2907 ACS Applied Materials & Interfaces 14 2 2893 2907 N scie scopus 000742118200001 2-s2.0-85122649878 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article; Early Access CARBON-DIOXIDE CAPTURE DDR ZEOLITE SILICA DDR SEPARATION CO2/CH4 TEMPLATE MOLECULES PARTICLES INSIGHTS DRY KEYWORDS hybrid zeolite membrane heteroepitaxial growth biogas upgrading CO 2 permselectivities DDR zeolite module properties