In this study, ZSM-22 was synthesized using N,N-diethylaniline as a template through a hydrothermal method. The proton and various metals such as zirconium, strontium, and iron were immobilized on the surface of obtained zeolites through the ion exchange method. The catalysts were studied by Fourier-Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption isotherms, Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) elemental analysis, and Temperature-Programmed Desorption of ammonia (TPD-NH₃) technique for determining the number of acid sites. In the esterification reaction of oleic acid, the operating conditions such as catalyst dosage, temperature, molar ratio of methanol to oil, and reaction time were optimized and adjusted at 11 wt%, 70°C, 10 : 1, and 48 h subsequently. The maximum yield% of 48.07% was achieved in the presence of Zr-H-ZSM-22 at optimum conditions. In order to improve the efficiency of three zeolites Zr-H-ZSM-22, Fe-H-ZSM-22, and Sr-H-ZSM-22, the core-shell structures with SiO₂ coating were prepared. Zr-H-ZSM-22@SiO₂ was less active than Zr-H-ZSM-22 due to the SiO₂ coverage of Lewis active sites.

中文翻译：

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负载金属的 H-ZSM-22 的二氧化硅涂层形成核壳纳米结构：油酸酯化中的表征、结构特性和催化效力

本研究以N,N-二乙基苯胺为模板，通过水热法合成了ZSM-22。通过离子交换方法将质子和各种金属如锆、锶、铁固定在所得沸石的表面。通过傅里叶变换红外光谱 (FT-IR)、X 射线衍射 (XRD)、Brunauer-Emmett-Teller (BET) 吸附等温线、透射电子显微镜 (TEM)、扫描电子显微镜 (SEM)、感应耦合等离子体发射光谱 (ICP-OES) 元素分析和氨程序升温脱附 (TPD-NH ₃₎) 确定酸性位点数量的技术。在油酸酯化反应中，对催化剂用量、温度、甲醇与油的摩尔比、反应时间等操作条件进行了优化调整，依次为11wt%、70℃、10:1、48h。在 Zr-H-ZSM-22 存在的最佳条件下，最高产率为 48.07%。为了提高Zr-H-ZSM-22、Fe-H-ZSM-22和Sr-H-ZSM-22三种沸石的效率，制备了具有SiO ₂涂层的核壳结构。由于路易斯活性位点的 SiO ₂覆盖，Zr-H-ZSM-22@SiO _{2 的}活性低于 Zr-H-ZSM-22 。