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在NaF-Na_2O-Al_2O_3-SiO_2-H_2O体系中合成了ZSM-5沸石。当NaF/(2Na_2O+NaF)=0.500—0.655时,得到纯ZSM-5沸石,该比值小于0.440时得到丝光沸石;大于0.440小于0.500时得到ZSM-5和丝石沸石混晶。研究了NaF量、碱度和温度对合成ZSM-5沸石的影响,得到成核表观活化能E_n=23.5千卡/摩尔,结晶表观活化能E_c=18.7千卡/摩尔。用扫描电子显微镜和透射电子显微镜观察了不同温度、碱度和氟化钠用量对晶粒大小分布的影响,以及凝胶粒子随晶化时间的延长由大变小,ZSM-5晶粒由小变大的全过程。
ZSM-5 zeolite was synthesized in NaF-Na 2 O-Al 2 O 3 -SiO 2 -H 2 O system. When NaF / (2Na_2O + NaF) = 0.500-0.655, pure ZSM-5 zeolite is obtained, and when the ratio is less than 0.440, mordenite is obtained; and when the ratio is greater than 0.440 and less than 0.500, the mixed crystal of ZSM-5 and zeolite zeolite is obtained. The effects of NaF, alkalinity and temperature on the synthesis of ZSM-5 zeolite were studied. The apparent activation energy E_n was 23.5 kcal / mol, and the apparent activation energy E_c was 18.7 kcal / mol. The effects of different temperature, alkalinity and sodium fluoride dosage on the grain size distribution were observed by scanning electron microscopy and transmission electron microscopy. The results showed that the grain size of the ZSM-5 crystal decreased from large to small as the crystallization time prolonged. Bigger the whole process.