四丙基氢氧化铵处理钛硅分子筛催化1-己烯环氧化  

Effect of TS-1 Treatment by Tetrapropyl Ammonium Hydroxide on 1-Hexene Epoxidation

作　　者：王亚权[1,2,3] 林永杰[1,2,3] 刘伟[1,2,3] 王书海[1,2,3] 叶家鑫 李昊阳[1,2,3] 王守桂 Wang Yaquan;Lin Yongjie;Liu Wei;Wang Shuhai;Ye Jiaxin;Li Haoyang;Wang Shougui(Key Laboratory for Green Chemical Technology of Ministry of Education,Tianjin 300072,China;School of Chemical Engineering and Technology,Tianjin University,Tianjin 300072,China;Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin 300072,China)

机构地区：[1]绿色化学工艺教育部重点实验室,天津300072 [2]天津大学化工学院,天津300072 [3]天津化学化工协同创新中心,天津300072

出　　处：《天津大学学报（自然科学与工程技术版）》2017年第1期65-70,共6页Journal of Tianjin University：Science and Technology

基　　金：国家自然科学基金资助项目(21276183)~~

摘　　要：用不同浓度的四丙基氢氧化铵(TPAOH)处理钛硅分子筛(TS-1),处理后的钛硅分子筛作催化剂催化1-己烯发生环氧化反应.用X射线粉末衍射(XRD)、傅里叶变换红外光谱(FT-IR)、紫外漫反射(UV-Vis)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、N2吸附-脱附曲线(BET)、氨气程序升温脱附(NH3-TPD)和电感耦合等离子体发射光谱(ICP)对催化剂进行了表征.表征结果表明:样品的MFI结构没有被破坏;当TPAOH碱处理钛硅分子筛时,晶体内部部分硅溶解导致分子筛内部有介孔生成;随着四丙基氢氧化铵浓度的增加,分子筛中的骨架钛含量逐渐减少同时有非骨架钛生成.在催化1-己烯环氧化反应中,介孔的生成使处理后的钛硅分子筛活性和选择性得到明显改善.但是当介孔体积大于0.219,cm3/g时,由于骨架钛损失较多,1-己烯转化率和1,2-环氧己烷相对于1-己烯和过氧化氢的选择性都显著降低.Titanium silicalite-1(TS-1)was treated by tetrapropyl ammonium hydroxide(TPAOH)with different concentrations and used as catalyst in 1-hexene epoxidation.All the samples were characterized by X-ray powder diffraction(XRD),Fourier-transform infrared spectrum(FT-IR),ultraviolet-visible diffuse reflectance spectrum (UVVis),scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen physical adsorption and desorption(BET),NH3-temperature programmed desorption(TPD)and inductively coupled plasma atomic emission spectrometry(ICP).The results show that the MFI structures of the samples are not destroyed and mesopores are formed in TS-1 crystals due to the dissolution of silica when TS-1 samples are treated by TPAOH.However,the framework Ti content decreases gradually,forming extraframework Ti. Due to the formation of mesopores,the catalytic activity and selectivity of the treated TS-1 are markedly improved in the reaction of 1-hexene epoxidation.However,when the volumes of the mesopores are larger than 0.219 cm3/g,the 1-hexene conversion and the selectivities of 1,2-epoxyhexane to 1-hexene and H2O2 sharply decrease as a result of the appreciable loss of the framework Ti in the TPAOH treatment.

关 键 词：钛硅分子筛 四丙基氢氧化铵 1-己烯环氧化 介孔 

分 类 号：O643.36[理学—物理化学]