Co-MCM-48的制备及其对烯烃环氧化催化性能的研究

Synthesis of mesoporous Co-MCM-48 and its catalytic performance in the epoxidation of olefin

通过水热合成法合成了掺杂过渡金属元素Co的介孔材料MCM-48,然后通过傅里叶变换红外(FT-IR)波谱、X-射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、N_2吸附-脱附等温线对其进行了表征,并以环己烯为底物,分别用w(过氧化氢)=30%和过氧乙酸作氧源对其烯烃环氧化的催化性能作了研究。催化剂的表征结果表明,合成的介孔材料结构规整。将合成的杂原子分子筛用于催化烯烃的环氧化反应,反应结果表明,w(过氧化氢)=30%和过氧乙酸相比,w(过氧化氢)=30%使反应达到了更好的转化率,但对环氧化物的选择性远远不如过氧乙酸,几乎没有目标产物环氧化物的生成。这可能是由于w(过氧化氢)=30%更容易被活化,但是也更容易发生环氧化物进一步的开环反应,从而导致极少目标产物环氧化物的生成。

Co-MCM-48 was synthesized, and characterized by FT-IR spectra, X-ray diffraction（XRD）, Scanning electron microscope,Transmission electron microscope,N2 adsorption-desorption isotherms. Then we studied its catalytic performance in the reaction of olefin epoxidation, using 30% H2O2 and CH3CO3 H as oxidants respectively. The characterization of catalyst showed that an ordered material was synthesized. The result of the reaction catalyzed by Co-MCM-48 using two different oxidants was as follows：compared to CH3CO3H,the reaction using 30% H2O2 as oxdidant got higher conversion, but was far less selective to get epoxide. Maybe this was because of that 30% H2O2 was easier to be activated,but also easier to make the ring-open reaction happen, thereby we got very little epoxide.