摘要
研究了低硅铝比X型(LSX)分子筛的合成体系和控制方法,探究了引入功能性物质制备高纯度、可调晶簇尺寸的LSX分子筛的可行性,通过优化分子筛水热反应配方和条件确定了制备LSX分子筛的技术方案并初步考察了晶簇尺寸与活性的关联性,进而采用工业原料实现了高品质LSX分子筛的合成。实验结果表明,在钾-钠双元体系中借助低温老化—高温晶化两段法可制备LSX分子筛;老化温度/时间、晶化温度/时间、硅铝比、碱硅比、水碱比及钠钾比能显著影响分子筛的合成过程;向反应体系中引入适当功能性物质可制备出结晶度高、含杂晶量少、活性佳、平均晶簇尺寸在1~4μm可调的LSX分子筛;由此能优化得到适合分子筛生产的长、短流程两套技术方案,进一步明确了上述手段具有保证本征活性不变,通过减小晶簇尺寸改善吸附剂传质系数的操作可能性;使用工业原料制备出了合格的LSX分子筛,放大合成的产品仍满足制氧吸附剂要求。
The synthesis system of low silica-alumina X(LSX)molecular sieve and the control method for it were studied.The feasibility of introducing functional substances to prepare LSX molecular sieve with high purity and adjustable cluster sizes was explored.The technology schemes for LSX molecular sieve production were determined via optimizing the formulation and conditions for hydrothermal reactions of molecular sieve,and the correlation between cluster size and activity was also preliminarily investigated.Further,the synthesis of high-quality LSX molecular sieve using industrial materials was achieved.The experimental results show that LSX molecular sieve can be prepared by the two-stage method involving low temperature aging and high temperature crystallization in a potassium-sodium binary system.Aging temperature/time,crystallization temperature/time,n(SiO_(2))∶n(Al2O3),n(Na2O+K2O)∶n(SiO_(2)),n(Na2O)∶n(Na2O+K2O),n(H2O)∶n(Na2O+K2O)can significantly affected the synthesis process of molecular sieve.By introducing appropriate functional substances,LSX molecular sieve with high crystallinity,low heterocrystal content,good activity and adjustable average cluster size of 1-4μm can be prepared.From these,two technical schemes of long and short processes suitable for the molecular sieve production were obtained.It was also confirmed that improving the mass transfer coefficient of adsorbent without intrinsic activity reduction by decreasing the size of crystal clusters is operational.Qualified LSX molecular sieve are prepared with industrial materials and the product of scale-up synthesis still meet the requirements for oxygen production adsorbent.
作者
崔凯
吕芳芳
李柯志
石勤智
杨柳
杨振钰
CUI Kai;LV Fangfang;LI Kezhi;SHI Qinzhi;YANG Liu;YANG Zhenyu(Institute of Engineering Technology,Sinopec Catalyst Co.,Ltd.,Beijing 101100,China)
出处
《石油化工》
CAS
CSCD
北大核心
2024年第1期18-25,共8页
Petrochemical Technology
基金
中国石化催化剂有限公司科技开发项目(SCC-B-2022-019)。
关键词
低硅铝比
X型分子筛
制氧
制备技术
low silica-alumina ratio
X molecular sieve
oxygen production
preparation technology
