中文摘要：

系统研究了以KOH为结构导向剂,Y型沸石（HY和NaY）在水热条件下转晶为MER型沸石的行为.MER型沸石是硅铝比（Si/Al）在2~3之间且具有四种尺寸8元环孔道（3.1×3.5,2.7×3.6？,3.4×5.1,3.3×3.3）的硅铝沸石分子筛,在小分子催化以及分离方面具有重要的潜在应用.传统水热法合成高结晶度MER型沸石需要7-10 d,将Y型沸石置于KOH的溶液中,经水热处理可在2 d内生成高结晶度的MER型沸石,而水热处理具有等价摩尔组成的无定形硅铝凝胶则得不到高结晶度MER型沸石的纯相.HY沸石可在100和150℃发生转晶,而Na Y则只能在150℃发生转晶.KOH/SiO_2比和H_2O/SiO_2比对Y型沸石的转晶行为有重大的影响,只有在最优KOH/SiO2比和H_2O/SiO_2比条件下才能生成高结晶度的MER型沸石.该转晶合成法显著缩短了MER型沸石的合成周期,对缩短其它有重大工业应用价值的沸石分子筛的合成周期有重要的借鉴意义.

英文摘要：

The phase transition behavior of zeolite Y （HY and NaY） to zeolite MER in the KOH solution under hydrothermal conditions was systematically investigated. Zeolite MER has four types of 8-membered ring channels （3.1 A × 3.5 A, 2.7 A× 3.6 A, 3.4 A × 5.1 A, 3.3 A×3.3 A） and important potential applications in small molecule catalysis and separation. Seven to ten days are needed to synthesize highly crystalline zeolite MER with traditional hydrothermal synthesis. With phase transition of zeolite Y in the KOH solution under hydrothermal treatment, highly crystalline zeolite MER can be obtained within two days. The synthetic system contains zeolite Y （HY and NAY）, KOH, and water, where KOH/SiO2 and H20/SiO2 are changea- ble. Hydrothermally treating the equivalent amorphous aluminosilicate gel resulted in the mixture of zeolite MER and zeolite LTL （for HY） or zeolite CHA （for NaY） with low degree of crystallinity. Phase transition of HY can be conducted at either 100 or 150℃, whereas that of NaY can only be conducted at 150℃. As a common process for the hydrothermal phase transition of zeolite Y to zeolite MER in the absence of organic templates, potassium hydroxide was first dissolved into deionized H20. After stirring at room temperature for 5 min, zeolite Y （HY or NaY） as aluminum and silicon sources was introduced into the potassium hydroxide solution. After further stirring for 1 h, the mixre was transferred into an autoclave for crystallization at elevated temperature （i.e. 100 or 150 ℃）. After filtrating, washing with deionized water and drying, zeolite products were obtained. The zeolite products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, thermo- gravimetric analysis （TGA）, and inductively coupled plasma emission spectrometer （ICP）. KOH/SiO2 and H2O/SiO2 have sig- nificant influence on the phase transition behavior of zeolite Y. Highly crystalline zeolite MER can only be obtained with the optimized KOH/SiO2 and H20/SiO2.