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在TMEDA(四甲基乙基二胺)-Na_2O-SiO_2-Al_2O_3-H_2O体系(Ⅰ),Na_2O-K_2O-Al_2O_3-SiO_2-H_2-HCO_3~-CO_3~(2-) (Ⅱ)及Py(吡啶)-PrNH_2(正丙胺)-HF-SiO_2-H_2O体系(Ⅲ)中,分别合成了纯相FER沸石及FER硅沸石.用粉末XRD,FT-IR,~(29)Si MAS NMR及TG/DTA等表征其结构性质,并用超微量电子真空吸附天平测定这些沸石样品对正己烷,甲醇和水的吸附等温线.结果表明:各体系合成的样品虽然结晶度高,呈现出FER沸石的典型结构特征,但由于它们的组成和晶格微结构不同,热稳定性与吸附性质有明显的差异.在(Ⅰ)体系中合成的FER沸石层错缺陷少,晶格完美,正己烷与甲醇的吸附量可达到理论值,结构破坏温度为1190℃.红外精细谱及~(29)Si MAS NMR高分辨谱证明FER硅沸石具有十分完美的骨架结构.由于晶胞收缩,它对正己烷与甲醇吸附量略低于理论值,并呈现出高度的疏水性.它的结构破坏温度高于1300℃.在(Ⅱ)体系中合成的FER型沸石结构缺陷多,沸石孔中的钾离子不易被质子完全交换.它的正己烷与甲醇吸附量均较低,而水的吸附量相对较高.吸附现象表明,正己烷和甲醇都被吸附于FER沸石的十元环主孔道中,分压较高时,甲醇可通过八元环进入小笼,而水的吸附性质则主要与各样品的Si-OH缺陷及骨架中的阳离子含量有关.
In the system of TMEDA (tetramethylethyldiamine) -Na 2 O-SiO 2 -Al 2 O 3 -H 2 O (Ⅰ), Na 2 O-K 2 O-Al 2 O 3 -SiO 2 -H 2 -HCO 3 ~ -CO 3 ~ (2-) (Ⅱ) and Py ) -PrNH_2 (n-propylamine) -HF-SiO_2-H_2O system (Ⅲ), the pure phase FER zeolite and the FER zeolite were synthesized respectively.The structures of the samples were characterized by XRD, FT-IR, ~ 29 Si MAS NMR and TG / DTA Etc. The adsorption isotherms of n-hexane, methanol and water were determined by using ultra-trace electron vacuum adsorption balance.The results show that the samples synthesized by each system have high crystallinity and show the typical structural features of FER zeolite , But their thermal stability and adsorption properties are obviously different due to their composition and lattice microstructures. In the system of (Ⅰ), the FER zeolite synthesized has fewer defects and defects, the crystal lattice is perfect, the adsorption amount of n-hexane and methanol Up to the theoretical value, the temperature at which the structure destructs is 1190 ° C. High-resolution infrared spectroscopy and ~ (29) Si MAS NMR demonstrate that FER silicalite has a very perfect framework structure. Due to the shrinkage of the unit cell, Slightly lower than the theoretical value, and showed a high degree of hydrophobicity, its structural failure temperature is higher than 1300 ° C. In the (Ⅱ) system synthesized FER Zeolite has many structural defects, and the potassium ions in zeolite pores are not easily exchanged by protons, and the adsorption amount of n-hexane and methanol is low, while the adsorption amount of water is relatively high.The adsorption phenomenon indicates that n-hexane and methanol are adsorbed to FER zeolite ten-ring main channel, the partial pressure is higher, the methanol can be eight yuan into the cage, and water adsorption properties are mainly associated with each sample Si-OH defects and the cation content of the skeleton.