In this work, we demonstrate a facile approach for the synthesis of zeolite-Y crystals (size, ca. ∼400 nm) supported on silicon carbide (SiC) with the assistance of the cationic template (polydiallyldimethylammonium chloride, PDDA). The polymeric cationic template used to treat SiC particles induces a positive charge on SiC surface which electrostatically attracts negatively charged aluminosilicate seeds and promotes the growth of zeolite (ZY) particles over SiC, thus leading to the formation of stable ZY@SiC supported catalysts. The supported ZY catalysts with different weight ratio of ZY and SiC were synthesized and characterized by various techniques such as XRD, SEM, SEM-EDX, SEM-mapping, TEM, STEM, FT-IR, ²⁷Al MAS NMR and N₂ sorption. The characterization of the supported ZY catalysts suggests the uniform growth of ZY particles over SiC together with the creation of hierarchical micro-mesopores assembly. In the catalytic cracking of n-heptane, the catalyst ZY@SiC-50 displayed a remarkable improvement in reaction rate when compared to commercial zeolite-Y (CBV-600) amounting to 3.5 folds enhancement. Interestingly, the light olefins yield is also substantially improved. At WHSV of 8 h⁻¹ and 475 °C, the highest light olefin yield (24–36 %) was achieved over ZY@SiC-50 whereas the reference catalyst, CBV-600 produced lower light olefins yield (7–17 %). Moreover, the supported ZY catalyst exhibited less deactivation rates. This improved performance is attributed to the hierarchical micro-mesopores assembly created by the homogeneous dispersion of zeolite crystals on SiC which offers fast diffusion pathways for the reactants and enhanced accessibility to active sites thus leading to higher observed reaction rates and fast diffusion of products thus minimizing the occurrence of side reactions.

在这项工作中，我们展示了一种在阳离子模板（聚二烯丙基二甲基氯化铵，PDDA）的辅助下合成载于碳化硅（SiC）上的沸石-Y晶体（尺寸约400 nm）的简便方法。用于处理SiC颗粒的聚合阳离子模板可在SiC表面感应出正电荷，从而静电吸引带负电的硅铝酸盐种子，并促进沸石（ZY）颗粒在SiC上的生长，从而导致形成稳定的ZY @ SiC负载型催化剂。通过XRD，SEM，SEM-EDX，SEM-mapping，TEM，STEM，FT-IR，²⁷ Al MAS NMR和N ₂等多种技术合成和表征了ZY与SiC不同重量比的负载型ZY催化剂。吸附。负载型ZY催化剂的特性表明ZY颗粒在SiC上均匀生长，并产生了分层的微孔组合。在正庚烷的催化裂化中，与商用沸石-Y（CBV-600）相比，催化剂ZY @ SiC-50的反应速率显着提高了3.5倍。有趣的是，轻烯烃的产率也大大提高了。在WHSV为8 h ^-1在475°C下，轻质烯烃的最高收率（24–36％）高于ZY @ SiC-50，而参考催化剂CBV-600产生的轻质烯烃的收率较低（7–17％）。而且，负载的ZY催化剂表现出较小的失活速率。这种改进的性能归因于沸石晶体在SiC上的均匀分散所产生的分层微介孔组件，该组件为反应物提供了快速扩散途径，并增加了对活性位点的可及性，从而导致更高的观察到的反应速率和产物的快速扩散，从而使产物最小化副反应的发生。