摘要 在本研究中我們預備以先前發展出之快速製作奈米silicalite-1 沸石的方法，進一步合成出含鋁之ZSM-5 沸石。 此一方法乃是將前驅物先濃縮到約30wt% SiO2，將此濃稠前驅物在80℃老化約一天後再以175℃水熱反應進行合成。合成ZSM-5 沸石前，我們必須先更清楚地瞭解製備過程中條件之控制。例如，在濃縮程序的操控步驟、溫度與時間，以及濃縮後的加熱條件。有此部分了解後我們又進行合成ZSM-5 沸石，我們研究在起使配方中之Si/Al比與 TPAOH/Si比例對於合成ZSM-5 沸石大小的影響。發現到當系統中鋁含量增加時，合成出之沸石粒子尺寸也增加。TPAOH之比例在系統中亦有一理想比例，在此比例下合成出之ZSM-5 沸石粒子尺寸最小。在適當之合成條件下我們可在兩天內製備出大小分別為140、110 與50nm之ZSM-5（silicalite）奈米沸石，其Si/Al比分別為50、100 與∞。 Abstract A procedure was developed in our laboratory to synthesis non-agglomerated silicalite nanocrystals within days, instead of weeks as required in the literatures. This was achieved by concentrating the precursor sol, aging at 80oC for about a day, followed by a short hydrothermal reaction at 175oC. In this study, the same procedure has been extended to the synthesis of aluminum containing ZSM-5 zeolite nanocrystals. However, before applying the method to ZSM-5 system, some details of the previous procedures were further investigated to clarify the controlling parameters. For example, the proper way to concentrate the precursor sol, the selection of temperature and duration in the first aging stage, as well as that in the second hydrothermal reaction stage. After clarifying the controlling parameters, the method was applied to the synthesis of ZSM-5. In addition to the Si/Al ratio, the effect of TPAOH ratio in the starting recipe was also investigated. It was found that the size of the resulted nanozeolite increases with the amount of aluminum incorporated. On the other hand, there exists an optimum TPAOH/SiO2 ratio leading to the smallest particles size. Under appropriate conditions,non-agglomerated ZSM-5 (silicalite) nanocrystals of 140, 110 and 50 nm for Si/Al of 50, 100 and infinite, respectively, were achieved with a total synthesis time shorted than 2 days.
