Abstract Despite the high application potential in many important separation processes, high membrane cost is a leading obstacle for the commercial application of zeolite membranes. Compared with conventional hydrothermal synthesis, gel-less method has advantages like high material efficiency and easy control of membrane thickness. However, the development of gel-less method was limited to Silicalite-1 and A membranes due to the poor understanding of membrane formation mechanism and controlling parameters. Herein, we systematically investigated the effect of various parameters on the gel-less synthesis of SSZ-13 membranes for the first time. The obtained membranes were characterized by XRD, SEM, and CO2–CH4 separation. The key to the successful gel-less synthesis is to create an environment similar to that of conventional hydrothermal synthesis, which requires a delicate equilibrium between the template solution in the seed layer and the template solution at the bottom of autoclave. The thickness of SSZ-13 membrane can be controlled between 0.7−1.7 μm by manipulating the seed concentration in the dip-coating suspension. The obtained SSZ-13 membranes demonstrated high CO2 permeance 1.4–3.4 × 10−6mol/(m2⋅s⋅Pa) with decent CO2–CH4 selectivity of 35–116 at room temperature and 0.14 MPa.

中文翻译：

---

通过无凝胶法高效合成薄 SSZ-13 膜

摘要 尽管在许多重要的分离过程中具有很高的应用潜力，但高昂的膜成本是沸石膜商业化应用的主要障碍。与传统的水热合成相比，无凝胶法具有材料效率高、膜厚易于控制等优点。然而，由于对成膜机制和控制参数的了解不足，无凝胶方法的发展仅限于 Silicalite-1 和 A 膜。在此，我们首次系统地研究了各种参数对 SSZ-13 膜无凝胶合成的影响。通过XRD、SEM和CO2-CH4分离对所得膜进行表征。成功无凝胶合成的关键是创造一个类似于传统水热合成的环境，这需要种子层中的模板溶液和高压釜底部的模板溶液之间存在微妙的平衡。通过控制浸涂悬浮液中的种子浓度，SSZ-13 膜的厚度可以控制在 0.7-1.7 μm 之间。获得的 SSZ-13 膜表现出高 CO2 渗透率 1.4-3.4 × 10-6mol/(m2⋅s⋅Pa)，在室温和 0.14 MPa 下具有 35-116 的 CO2-CH4 选择性。