摘要
分别在常规水热晶化条件与氟离子存在下合成了铁离子取代的磷铝分子筛(FeAPO-5),并用X射线衍射仪(XRD)、扫描电镜(SEM)、傅立叶红外光谱(FT-IR)、紫外漫反射可见光谱(UV-vis)、顺磁共振(ESR)和H_2程序升温还原实验(H_2-TPR)等对分子筛样品进行了表征。结果表明,氟离子存在下合成的FeAPO-5分子筛样品的结晶度提高,比表面积明显增大。两种条件下合成的FeAPO-5样品中铁离子主要位于分子筛的骨架上,但氟离子存在下合成的分子筛具有更多的不饱和配位Fe(Ⅲ)。氟离子存在下合成的FeAPO-5分子筛在苯酚羟基化反应过程中具有良好的催化性能,明显优于常规水热晶化合成的分子筛。
Iron-substituted aluminophosphate molecular sieves （FeAPO-5） were synthesized by hydrothermal crystallization conventionally or in the presence of fluoride ion, respectively. Those synthesized molecular sieves were characterized by X-ray diffraction （XRD）, scanning electron spectroscopy （ SEM ）, Fourier transform infrared （ FT-IR ） spectrometer, ultraviolet visible spectroscopy （UV-vis）, electron spin resonance （ESR） and hydrogen termperature programmed reduction （H2-TPR）. The results revealed that the crystallinity and BET of synthesized samples increased apparently in the presence of F^＋. The Fe^3＋ was mainly present in the framework sites of FeAPO-5 molecular sieves, but more unsaturated co-ordinate framework Fe （Ⅲ） was present in FeAPO-5 by adding HF. Moreover, the FeAPO-5 synthesized in the presence of F^＋ exhibited higher catalytic activity in the phenol hydroxylation than that of synthesized conventionally.
出处
《化学反应工程与工艺》
EI
CAS
CSCD
北大核心
2007年第6期548-552,559,共6页
Chemical Reaction Engineering and Technology
基金
教育部高校博士点科研基金(20040291005)
关键词
分子筛
氢氟酸
合成
苯酚羟基化
molecular sieve
hydrogen fluoride
synthesis, phenol hydroxylation
