【摘要】 以B-ZSM-5沸石为母体,经过脱硼处理后,在高温下与TiCl4进行气-固相取代合成钛硅沸石Ti-ZSM-5,考察了母体n(SiO2)/n(B2O3)对钛进入骨架的影响。以XRD、FT-IR、UV-Vis、XRF、Raman、ICP-AES和NH3程序升温脱附(TPD)等手段表征了催化剂,并考察了其丙烯环氧化性能。结果表明,随着母体n(SiO2)/n(B2O3)的增加,所制得的Ti-ZSM-5的n(SiO2)/n(TiO2)增大,即总钛含量降低;随着母体n(SiO2)/n(B2O3)的增加,所制备的Ti-ZSM-5的丙烯环氧化活性降低,而环氧丙烷的选择性增大。当以n(SiO2)/n(B2O3)=100的样品为母体时,制得Ti-ZSM-5中含有较多的锐钛矿型TiO2。更多还原

【Abstract】 Ti-ZSM-5 samples were successfully synthesized by using B-ZSM-5 with different n(SiO2)/w ( B2O3 ) ratios as precursors. The gas-solid synthesis of Ti-ZSM-5 included two steps: deboronated in HC1 solution firstly, then titanated with TiCl4. The effect of n(SiO2)/ n(B2O3) on the incorporation of titanium into the framework were investigated. The synthesized titanium- containing samples were thoroughly characterized by X-ray diffraction (XRD), Fourier-transformed infrared ( FT-IR ), X-ray fluorescence ( XRF), UV Vis spectroscopy, Raman spectroscopy, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and NH3 temperature programmed desorption (TPD). Propylene epoxidation properties were also investigated. The results showed that, n(SiO2 )/n(TiO2 ) in the product samples increased with the increase in the n(SiO2 )/n(B2O3) of the precursors; The conversion of H2O2 increased with the decrease of the n(SiO2 )/n(B2O3) of the precursor or the n(SiO2)/ n(TiO2) of the product, at the same time, the selectivity to propylene oxide (PO) decreased. Anatase appeared in Ti-ZSM-5 sample synthesized by using B-ZSM-5 with n(SiO2 )/n(B2O3) of 100 as the precursor.更多还原