| 晶种法高效合成低硅铝比LSX型分子筛 | |
| High Efficient Seeding Synthesis of LSX Molecular Sieve with Low Si-Al Ratio | |
| 摘要: 分别以工业级的偏铝酸钠和水玻璃为铝源和硅源，氢氧化钠为主要碱源，氢氧化钾为辅助碱源，采用LSX晶种法制备了LSX型分子筛。通过X射线衍射（XRD）、扫描电子显微镜（SEM）、X射线荧光（XRF）、傅里叶变换红外光谱（FTIR）和N2吸附-脱附等表征方式考察了有无晶种、钾钠物质的量之比、晶化条件对合成LSX型分子筛的影响。结果表明，加入LSX晶种不仅能显著缩短晶化时间，提高分子筛的结晶度，还可有效抑制方钠石和A型杂晶的伴生；钾钠比过高或过低均会造成A型或方钠石型杂晶的伴生；直接进行高温晶化会导致亚稳态的LSX型分子筛向热力学稳定相转变；延长老化时间或高温晶化处理降低了产物中的硅铝比；样品的比表面积和N2吸附量随老化时间的延长和高温晶化处理而逐渐下降。 | |
| 关键词: LSX分子筛 晶种法 低成本 高效率 | |
| 基金项目: 国家自然科学基金（No.41206067）资助项目。 | |
| Abstract: Influencing factors for the synthesis of LSX molecular sieve, such as LSX seed, nK/nNa and crystallization conditions were investigated in detail. The products were characterized by XRD, SEM, XRF, FTIR and N2 adsorption-desorption. The results revealed that the addition of LSX seed could accelerate the rates of crystal nucleation and growth, and inhibit the formation of A type and sodalite zeolites. Furthermore, too high or too low value of nK/nNa in the synthesis gel would obtain A type and sodalite impurities. Crystallization at high temperature directly would lead the conversion of metastable LSX zeolite into more thermodynamically stable zeolite phase. The Si-Al ratio, the surface area and N2 adsorption capacity of the end product decreased with the extending of aging time and the increasing of crystallization temperature. | |
| Keywords: LSX molecular sieve seeding method low-cost high efficiency | |
| 投稿时间：2016-07-10 修订日期：2016-09-21 | |
| 摘要点击次数: 2556 | |
| 全文下载次数: 1868 | |
| 赵东璞,张妍,李琢,于建强.晶种法高效合成低硅铝比LSX型分子筛[J].无机化学学报,2016,32(11):1995-2002. | |
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