气相转移法合成MnAPO-5分子筛

 采用气相转移法(VPT), 在含模板剂的干胶和液相体系中合成了具有AFI结构的MnAPO-5分子筛, 采用XRD、SEM、FT-IR、ICP、TG－DSC等手段对样品进行了表征. 考察了模板剂的添加方式、干胶中n(MnO)/n(Al₂O₃)、n(H₂O)/n(Al₂O₃)以及晶化温度和时间对所合成的MnAPO-5结晶度和热稳定性的影响. 结果表明, 在干胶和液相中均加入模板剂三乙胺, 有利于合成高结晶度的MnAPO-5,确并使焙烧后样品的热稳定性增强. 当干胶中n(MnO)/n(Al₂O₃)为0.1～0.2, n(H₂O)/n(Al₂O₃)为60～400,合成温度和时间分别为180～200℃和24～48h时, 有利于高结晶度MnAPO-5分子筛的形成.

SYNTHESIS OF METALLOALUMINOPHOSPHATE MOLECULAR SIEVES (MnAPO-5) BY VAPOR PHASE TRANSPORT TECHNIQUE

Metalloalμminophosphate molecular sieves with AFI topology (MnAPO-5) were synthesized by vapor phase transport (VPT) method, using dry gels containing the template and the liquid phase containing volatile organic amines. Systematic studies were carried out by varying the synthesis parameters such as the content of Mn metal, the way of adding the template, the amount of water, the reaction temperature and time. The products were characterized by XRD, SEM, FT-IR，ICP，BET and TG-DSC. The results indicated that MnAPO-5 with highest crystallinity could be synthesized by adding the template into both the dry gel and the liquid phase. When the MnO/Al2O3 molar ratio was from 0.1 to 0.2 and H2O/Al2O3 molar ratio from 60 to 400, pure MnAPO-5 could be synthesized at 180~200 ℃ for 24~48 h.