Ti-HMS-1分子筛的制备及其催化性能研究

Preparation of Ti-HMS-1 molecular sieve and its catalytic performance

采用TS-1前驱体作为硅源和钛源,以十二胺为结构导向剂,在室温条件下合成了含微孔结构单元的纯介孔分子筛TiHMS-1。采用X射线衍射(X-ray diffraction,XRD)、透射电子显微镜(transmission electron microscope,TEM)、傅里叶变换红外光谱(Fourier translation infrared spectrum,FT-IR)和紫外-可见(ultraviolet visible,UV-vis)等表征手段对合成的分子筛进行了表征。结果表明,所合成的Ti-HMS-1为纯介孔分子筛,钛原子全部进入了分子筛骨架,不存在骨架外钛;水热稳定性测试表明,将微孔结构单元引入介孔孔壁提高了其水热稳定性;首次采用Ti-HMS-1分子筛为催化剂,催化苯酚与碳酸二甲酯(dimethyl carbonate,DMC)合成碳酸二苯酯的反应,产物甲基苯基碳酸酯(methyl phenyl carbonate,MPC)和碳酸二苯酯(diphenyl carbonate,DPC)总选择性可达99.3%,此时苯酚的转化率为3.1%。

Pure mesoporous materials （Ti-HMS-1） with microporous zeolite structure unit can be assembled from titanosilicate-1 precursors with didecylamine （DDA） as structure directors. The obtained products were characterized by X-ray diffraction （XRD）, transmission electron microscope （TEM）, Fourier translation infrared spectrum （FT-IR）, ultraviolet visible （UV-vis） diffuse reflectance. The results show that Ti-HMS^I is a pure mesoporous phase, and the Ti atoms are incorporated into the framework and there are no Ti atoms outside of the framework. Hydrothermal stability test shows that the introduction of microporous pore structure element into the pore improves its thermal stability. Using Ti HMS-1 as the catalyst for the transesterification of dimethyl carbonate （DMC） with phenol, the totaI selectivity for methyl phenyl carbonate （MPC） and diphenyl carbonate （DPC） is 99.3% with a phenol conversion of 3.1%.