【作者】 杨建利；

【导师】 王水利；

【作者基本信息】 西安科技大学 ， 矿物加工工程， 2004， 硕士

【摘要】 超微沸石分子筛是目前分子筛领域的主要发展趋势之一。由于晶粒尺寸极小，超微沸石分子筛比普通沸石分子筛的外表面积和表面原子数明显增大、表面能增高、表面酸量增大、外露孔口增多、孔道缩短、孔容及孔隙率增加，因而表现出明显的体积效应、表面效应和量子尺寸效应,使其具有独特的物理化学性质。如何合成粒径更小甚至纳米级的超微低硅沸石分子筛是目前沸石合成领域的一个重要研究课题。本研究采用水热合成法，利用廉价的工业原料水玻璃代替正硅酸乙酯、白炭黑作硅源，普通化工原料碱金属盐、四氢呋喃、乙醇等代替昂贵的有机模板剂，系统地考察了各种外加助剂及其用量、晶化时间、晶化温度和搅拌速度对合成超微低硅沸石分子筛的影响。合成配比取Na2O﹕Al2O3﹕SiO2﹕H2O=3﹕1﹕2﹕185，合成产物分别由XRD、SEM、IR、激光粒度仪等手段进行了物相、形貌、结构及粒度分析，吸附量采用水中铵氮法测定。结果表明，在晶化温度85℃、晶化时间8小时、搅拌速度3000r/min(成胶)和1500r/min(成核)的合成条件下，分别加入0.1molNaBr、5%导向剂(陈化24h)和2%的四氢呋喃后，沸石结晶粒度由普通沸石的2μm减小为160nm、280nm和150～360nm；吸附总量由普通沸石的0.25mg/L增加为0.26～0.272ml/L；5min吸附量由普通沸石0.13mg/L增加为0.2～0.22mg/L。采用正交实验法考察了多种助剂对沸石结晶粒度的共同影响。结果表明，在85℃(4h)的结晶条件下，共同加入0.1molNaBr、2%四氢呋喃和3%导向剂(陈化时间24h)后，结晶粒度减小到120nm，晶化时间由8h减小为4h，而且晶化完全。更多还原

【Abstract】 Ultramicro zeolite molecular sieving is a main trend in the development of molecular sieving field at present. Because the crystalline grain size is very tiny, its outer surface area and the atom number of surface increased sharply, surface energy accreted, surface acid amount augmented, exposed ostiole augmented, aperture shortened, pore volume and pore rate improved, showing obvious volume effect, surface effect and quantum size effect lead to its special physical and chemical character. How to synthesize ultramicro low-silicon zeolite sieving which grain size less small even nanometer is layed store by scientists.This study adopts hydrothermal method, using inexpensive industry material such as sodium silicate substitute orthosilicate carbethoxyl and activated SiO2 for silicon source, common chemistry material alkali metal salt, tetrahydro furan, ethanol substitute for expensive organic template agent, screens systematically the effect when adding different blending agents and different adding quantity on conditions of temperature and time of crystallization and mixing speed. It is in proportion as composition of Na2O﹕Al2O3﹕SiO2﹕H2O=3﹕1﹕2﹕185. Through XRD expertizing phase, observing appearance, IR analyzing structure, laser analyzing granularity and measuring the absorption of ammonium and nitrogen in the water, it confirms adding 0.1molNaBr, 5% guide agent which seasons 24h and 2% tetrahydro furan separately under crystallization temperature 85℃, crystallization time 8h, mixing speed gelatigenous speed 3000r/min and nucleation speed 1500r/min, the crystallization granularities of synthesis zeolite are 160nm、280nm and 150～360nm separately by the contrast of the granularity of routine zeolite is 2μm; also its gross absorption comes at 0.26～0.272ml/L from 0.25mg/L of routine zeolite; The five minute absorption gets to 0.2～0.22mg/L from 0.13mg/L of routine zeolite.We adopt orthogonal experiment method to exam the togetherness effect on the crystallization granularity of zeolite by vary blending agent. The result shows adding simultaneously 0.1molNaBr、2% tetrahydro furan and 5% guide agent which seasons 24h under the crystallization temperature 85℃ and time 4h, its crystallization granularity comes <WP=4>at 120nm, crystallization time gets to 4h from 8h, moreover crystallizes completely.更多还原