NaA, NaY, ZSM-5, 그리고 beta등 총 4가지의 zeolite 분자체를 마이크로파 가열을 이용하여 합성하고 분자체 형성에 있어서 마이크로파 에너지의 기여 가능성을 검토하였다. 마이크로파 합성은 합성온도까지의 승온속도 증가율이 높기 때문에 일반적인 수열합성법에 비해 합성시간이 1/2-1/6까지 단축되었다. ZSM-5나 beta와 같은 zeolite의 경우 마이크로파 가열하에서는 Hofmann degradation의 증가로 template의 붕괴가 촉진된다. 따라서 마이크로파 합성의 경우, 일반적으로 수열합성 때보다 많은 유기 아민기의 증량이 필요하며, 이러한 점은 template의 높은 가격때문에 합성의 단점으로 작용한다. 한편, 시료의 조성은 그대로 유지한 채 H₂O만을 증량시켜주면 물의 높은 유전성질에 의하여 승온속도가 빨라졌으며 ZSM-5의 결정화도도 크게 증가하였다.

This report examines the preparation of four types of zeolites(NaA, NaY, ZSM-5, zeolite beta) under microwave heating conditions and discusses the possible contribution of microwave energy to the crystallization of molecular_x000D_ sieves. Preparation of zeolites attempted in this study showed that microwave synthesis technique can reduce the synthesis time to 1/2-1/6 of those required using conventional hydrothermal methods, primarily as a consequence of substantial enhancement in heating rate to synthesis temperature. For ZSM-5 and beta, in which organic amines are necessary as a template to generate a particular pore structure, microwave heating proved to have one undesirable aspect in that it also promotes the Hoffrnann degradation of the templates. As a consequence, for microwave synthesis, it was necessary to use the larger_x000D_ templates. Increasing the total amount of water, leaving the other substrate mole composition other than water fixed, induced faster heating rate to the synthesis temperature due to its high dielectric property and crystallinity of ZSM-5 was substantially increased.

Microwave Zeolite Synthesis NaA NaY ZSM-5 Zeolite Beta

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