模板分子TMEDA在CF-3及ZSM-39沸石笼中的位置及其与骨架的相互作用

用XRD、FTIR、IG-DTA、~(13)C魔角固体核磁共振表征了用四甲基乙基二胺(TMEDA)为结构异向剂合成的高硅沸石CF-3及ZSM-39.TMEDA不同基团的~(13)C化学位移,共振峰相对强度在交叉极化(CP)及高功率去偶(HPDEC)核磁共振谱中的变化,揭示出模板分子在尺寸不同的沸石笼中的位置、运动状态及其与骨架的相互作用.在ZSM-39沸石中的TMEDA分子,它的-C_2H_4-基团~(13)C共振峰明显窄化,向高场的异常位移以及它与-CH_3基团~(13)C共振峰相对强度在CP及HPDEC谱中的明显变化,说明为2个相邻的[5~(12)6~4]笼所共有的TMEDA分子,其-C_2H_4-基团与这2个笼所共用的六氧元环的氧原子有强烈的相互作用.

Position and Interaction with Framework for Template Molecule Tetramethyl ethyl enediamine Trapped in Cage of Zeolite CF-3 and ZSM-39

XRD, FT-IR, TG-DTA and 13C MAS NMR have been used to characterize silicon zeolite CF-3 and ZSM-39 hydrothermally crystallized in TMEDA-Na2O-SiO2-H2O system. The 13C chemical shift and the relative intensity of resonance peak in CP (cross polarization) and HPDEC(high power decoupling) NMR spectra for different group of TMEDA reveal the position, the moving and the interaction with framework for the template molecule trapped in different size cages of zeolites. The narrowness, the unusual chemical shift to high field, and the obvious change of the intensity for the 13C resonance peak of -C2H4- group related to that of -CH3 group in the CP and HPDEC spectra, indicate that one molecule of TMEDA is shared by two neighbours of [51264] cage of ZSM-39 and that the -C2H4- group of TMEDA interacts strongly with oxygen atoms locating at the 6-oxygen-membered ring between the two cages.