Ceramic Membrane Division, Central Glass & Ceramic Research Institute, CSIR, Jadavpur, Kolkata 700 032, India.
Ultrason Sonochem. 2013 Jan;20(1):314-21. doi: 10.1016/j.ultsonch.2012.07.012. Epub 2012 Aug 1.
NaP zeolite nano crystals were synthesized by sonochemical method at room temperature with crystallization time of 3h. For comparison, to insure the effect of sonochemical method, the hydrothermal method at conventional synthesis condition, with same initial sol composition was studied. NaP zeolites are directly formed by ultrasonic treatment without the application of autogenous pressure and also hydrothermal treatment. The effect of ultrasonic energy and irradiation time showed that with increasing sonication energy, the crystallinity of the powders decreased but phase purity remain unchanged. The synthesized powders were characterized by XRD, IR, DTA TGA, FESEM, and TEM analysis. FESEM images revealed that 50 nm zeolite crystals were formed at room temperature by using sonochemical method. However, agglomerated particles having cactus/cabbage like structure was obtained by sonochemical method followed by hydrothermal treatment. In sonochemical process, formation of cavitation and the collapsing of bubbles produced huge energy which is sufficient for crystallization of zeolite compared to that supplied by hydrothermal process for conventional synthesis. With increasing irradiation energy and time, the crystallinity of the synthesized zeolite samples increased slightly.
采用室温超声化学法合成了 NaP 沸石纳米晶体，结晶时间为 3h。为了进行比较，在相同的初始溶胶组成下，研究了常规合成条件下的水热法，以确保超声化学法的效果。NaP 沸石可以通过超声处理直接形成，而无需自生压力和水热处理。超声能量和辐照时间的影响表明，随着超声能量的增加，粉末的结晶度降低，但物相纯度保持不变。采用 XRD、IR、DTA-TGA、FESEM 和 TEM 分析对合成的粉末进行了表征。FESEM 图像表明，采用超声化学法可在室温下形成 50nm 的沸石晶体。然而，通过超声化学法随后进行水热处理，得到了具有仙人掌/白菜状结构的团聚颗粒。在超声化学过程中，空化的形成和气泡的坍塌产生了巨大的能量，足以促进沸石的结晶，而水热过程提供的能量不足以用于常规合成。随着辐照能量和时间的增加，合成沸石样品的结晶度略有增加。
