新型NU-85分子筛的物性表征与合成时间优化

Characterization, catalytic activity and synthesis time optimization of a novel molecular sieve NU-85

首次采用预置晶种法,以溴化六甲双铵(HMBr_2)为模板剂,(160～180)℃合成分子筛NU-85。采用XRD、SEM及FT-IR等表征手段对样品物性进行表征。结果表明,该合成样品NU-85分子筛为EU-1和NU-87共晶生长,具有典型的EU-1分子筛和NU-87分子筛的特征衍射峰,结晶度较高。SEM照片显示,合成NU-85分子筛形貌为较规整长方体的堆积层叠物,聚集现象较常见。实验考察NU-85分子筛的二甲苯异构化催化性能,发现产物具有较高的二甲苯异构化反应活性和选择性。

By seeding method and using N, N, N, N＇, N＇, N＇-hexamethyl-1,6-hexanediammomium （ hexamethonium） as the organic structure-directing agent, a novel molecular sieve NU-85 （EU-1/NU-87 two phase symbiotic molecular sieves）with certain Si/A1 ratio was synthesized at （ 160 - 180）℃ and characterized by XRD, SEM, and FT-IR. XRD results showed that there existed well-structured EU-1 and NU-87 molecular sieves in NU-85 molecular sieve and the typical characteristic diffraction peaks of EU-1 and NU-87 molecular sieves were observed; the crystallinity of NU-85 molecular sieve was higher. SEM results indicated that the morphology of NU-85 molecular sieve was well-structured accumulation of cuboid lamination. The catalytic properties of NU-85 molecular sieve for xylene isomerization were investigated and the results showed that NU-85 molecular sieve exhibited higher catalytic activity and selectivity.