CAJ | 학술논문

采用二次生长法在α-Al2O3载体上制备超薄型ZIF-8膜，研究了多种轻分子气体以及混合气体CO2/N2的渗透分离性能。通过SEM和XRD表征了ZIF-8晶种层的晶种涂布状态，以及ZIF-8晶体膜的生长覆盖度和晶膜厚度。研究结果表明：采用低浓度的晶种悬浮液通过浸润式连续多次涂布法，有利于获得晶种层厚度均匀且覆盖度高的超薄均匀ZIF-8晶种层，经过二次生长后所得ZIF-8膜的覆盖度高、厚度均匀且较薄，仅约为8.8μm；在所测试范围内的CO2/N2混合气体中，此ZIF-8膜对CO2具有优先选择透过性，其对CO2/N2的渗透分离因子随温度的升高而降低，随渗透压力的增加而增加，在298 K、406 kPa和CO2组分含量为50%时，该分离因子能达到6，显著超过Knudsen扩散的分离系数。
채용이차생장법재α-Al2O3재체상제비초박형ZIF-8막，연구료다충경분자기체이급혼합기체CO2/N2적삼투분리성능。통과SEM화XRD표정료ZIF-8정충층적정충도포상태，이급ZIF-8정체막적생장복개도화정막후도。연구결과표명：채용저농도적정충현부액통과침윤식련속다차도포법，유리우획득정충층후도균균차복개도고적초박균균ZIF-8정충층，경과이차생장후소득ZIF-8막적복개도고、후도균균차교박，부약위8.8μm；재소측시범위내적CO2/N2혼합기체중，차ZIF-8막대CO2구유우선선택투과성，기대CO2/N2적삼투분리인자수온도적승고이강저，수삼투압력적증가이증가，재298 K、406 kPa화CO2조분함량위50%시，해분리인자능체도6，현저초과Knudsen확산적분리계수。
Permeation and separation properties for CO2/N2 mixtures with high quality, thin (~8.8μm) zeolitic imidazolate framework-8 (ZIF-8) membranes prepared by the secondary growth method were studied at different temperatures and feed pressures. The crystal structure, surface coverage, uniformity of the prepared ZIF-8 seeding layers and membranes were characterized by using SEM and XRD. The low concentration of the seed suspension and subsequent dip-coating method helped to obtain a more uniform, continuous and ultrathin ZIF-8 seeds layer of support; the synthesized ZIF-8 membranes offered selective permeation for CO2over N2with CO2/N2 mixture feed under the experimental conditions studied. The separation factor of CO2/N2 mixed gas through a ZIF-8 film decreased with increasing temperature, but increased with increasing feed pressure. Its separation factor of CO2 over N2could reach 6 at 298 K, 406 kPa, and CO2 content of 50%, exceeding the Knudsen diffusion selectivity.