Silicalite-1 zeolite membranes were prepared on porous tubular α-Al₂O₃ supports by a secondary growth method. The influences of the Si/Al ratio and the amount of deposited MFI (silicalite-1 and ZSM-5) seed crystals on membrane pervaporation (PV) performance for the separation of ethanol/water (binary) and ethanol/water/succinic acid (ternary) mixtures were investigated. The prepared membranes were characterized by X-ray diffraction and scanning electron microscopy, and the Si and Al distributions in the membrane layers were determined by energy-dispersive X-ray line scanning. Each silicalite-1 membrane was composed of two layers: an MFI-seed-crystal layer that grew on the support surface, and another gel-derived silicalite-1 top layer that formed on the seed crystal layer. The texture of the MFI seed layer (i.e., the deposited amount and the Si/Al ratio) was found to play an important role in the separation process. When silicalite-1 seed crystals were used, the ethanol separation factor was high in the binary ethanol/water system, but lower in the presence of succinic acid. However, when ZSM-5 seeds were used, the ethanol separation factor in the ternary system improved. These results suggest that silicalite-1 membranes prepared using ZSM-5 seed crystals are effective for the recovery of ethanol in the presence of organic acids.

上多孔管状制备硅沸石-1沸石膜的α-Al ₂ ö ₃通过二次生长方法获得支持。Si / Al比和沉积MFI（silicalite-1和ZSM-5）籽晶的数量对膜渗透汽化（PV）性能的影响，用于分离乙醇/水（二元）和乙醇/水/琥珀酸（研究三元混合物。通过X射线衍射和扫描电子显微镜对所制备的膜进行表征，并通过能量色散X射线线扫描来确定膜层中Si和Al的分布。每个silicalite-1膜由两层组成：在支撑表面上生长的MFI晶种层，以及在籽晶层上形成的另一个凝胶衍生的silicalite-1顶层。发现MFI种子层的质地（即，沉积量和Si / Al比）在分离过程中起重要作用。当使用silicalite-1晶种时，在二元乙醇/水系统中乙醇分离系数较高，但在琥珀酸存在下较低。但是，当使用ZSM-5种子时，三元系统中的乙醇分离因子得到了改善。这些结果表明，使用ZSM-5晶种制备的silicalite-1膜可在有机酸存在下有效回收乙醇。