【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AlPO₄-34分子筛,考察了凝胶HF/Al₂O₃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、N₂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AlPO₄-34分子筛构成的圆柱条。表征结果显示,成型分子筛由2⁵μm的AlPO₄-34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。更多还原

【Abstract】 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.更多还原