预成型合成AlPO_4-34分子筛  

Pre-shaped synthesis of AlPO_4-34 molecular sieve monoliths

作　　者：王苹[1,2] 王从新 吕广[1,2] 马怀军[1] 曲炜 田志坚[1,3] Wang Ping;Wang Congxin;LüGuang;Ma Huaijun;Qu Wei;Tian Zhijian(Dalian National Laboratory for Clean Energy,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian Liaoning 116023,China;University of Chinese Academy of Sciences,Beijing 100049,China;State Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian Liaoning 116023,China)

机构地区：[1]中国科学院大连化学物理研究所洁净能源国家实验室,辽宁大连116023 [2]中国科学院大学,北京100049 [3]中国科学院大连化学物理研究所催化基础国家重点实验室,辽宁大连116023

出　　处：《石油化工》2018年第4期307-314,共8页Petrochemical Technology

基　　金：国家重点研发计划项目(2017YFB0306701);国家自然科学基金资助项目(21406224)

摘　　要：利用拟薄水铝石、磷酸、氢氟酸、1-甲基咪唑和水混合制得凝胶并挤条成型,将成型凝胶在1-甲基-3-乙基溴化咪唑离子液体中晶化制得成型的AlPO_4-34分子筛,考察了凝胶HF/Al_2O_3摩尔比、晶化时间、晶化温度等对制得分子筛的影响,采用XRD、SEM、颗粒强度测试、N_2吸附/脱附、NMR和TG等方法对成型分子筛进行表征。实验结果表明,保持凝胶中适当的HF量、延长晶化时间和提高晶化温度有利于得到机械强度高、结晶度高、完全由AlPO_4-34分子筛构成的圆柱条。表征结果显示,成型分子筛由2~5μm的AlPO_4-34分子筛晶粒构成,结晶度高,具有微孔、介孔和大孔的多级孔结构,机械抗压强度可满足固定床使用要求。The pseudo-boehmite,phosphoric acid,hydrofluoric acid,1-methylimidazole and water were mixed to prepare a gel and subjected to extrusion molding.AlPO4-34 molecular sieve monolith was directly synthesized with pre-shaped gel extrudates in 1-ethyl-3-methyl imidazolium bromide([EMIm]Br).The influence of various synthesis parameters(HF/Al2O3 molar ratio,crystallization time and temperature)on the synthesis of monolithic AlPO4-34 molecular sieve was investigated.XRD,SEM,particle mechanical strength test,N2 adsorption/desorption,NMR and TG analyses were used to characterize the properties of the molecular sieve.Maintaining a proper HF amount,prolonging the crystallization time and improving the crystallization temperature were beneficial to get a cylinder bar formed fully with the AlPO4-34 molecular sieve monolith with high crystallinity and mechanical strength.The obtained monolith was composed of compactly packed and intergroup 2-5μm AlPO4-34 molecular sieve crystals with abundant micro-,meso-,and macropores.The mechanical compressive strength could meet the requirement of fixed bed.

关 键 词：预成型 分子筛 AlPO4-34 离子液体 

分 类 号：TQ424.29[化学工程]