Bi_2SiO_5/SiO_2的合成及催化丙烯气相环氧化反应  

Synthesis of Bi_2SiO_5/SiO_2 catalyst for epoxidation of propylene in gas-phase

作　　者：张玉平[1] 陈晓晖[1] 魏可镁[1] 

机构地区：[1]福州大学化学化工学院化肥催化剂国家工程研究中心,福建福州350002

出　　处：《工业催化》2012年第7期1-5,共5页Industrial Catalysis

基　　金：国家自然科学基金(20976030)资助项目

摘　　要：水热法合成了具有介孔特征的系列Bi2SiO5/SiO2催化剂(记为SBn,n为Si与Bi物质的量比,n=0.5、5、10、20、50),并通过X射线粉末衍射、N2物理吸附-脱附和扫描电镜等技术对SBn催化剂进行表征。结果表明,以O2为氧源,SBn催化剂在气相丙烯环氧化反应中具有良好的催化活性。在温度330℃,SB20催化剂上环氧丙烷选择性达50%,对应丙烯转化率为0.6%;而在温度470℃时,SB20催化剂上丙烯转化率接近20%,但环氧丙烷选择性降至20%。Bi2SiO5/SiO2 （labeled as SBn,in which n was the molar ratio of Si to Bi） catalysts with different Si/Bi molar ratio （n =0.5,5,10,20,50） were synthesized by hydrothermal method. The SBn catalysts were characterized by X-ray diffraction, N2 adsorption-desorption and scanning electron microscopy. The results showed that SBn catalysts exhibited excellent catalytic activity in gas-phase propene epoxidation to propylene oxide by molecular oxygen. The selectivity to propylene oxide of 50% and propylene conversion of 0.6% were obtained over SB20 catalyst at 330℃. When the conversion of propylene approached to 20% over SB20 at 470℃ ,the selectivity to propylene oxide was decreased to 20%.

关 键 词：催化化学 硅酸铋 气相环氧化 环氧丙烷 丙烯 

分 类 号：O643.36[理学—物理化学] TQ426.94[理学—化学]