摘要
以纳米Fe_3O_4为磁核,分别采用溶胶-凝胶法和氟钛酸铵还原的液相沉积法制备了高磁性核壳式结构的Fe_3O_4/TiO_2复合颗粒;利用X射线衍射、透射电子显微镜、磁滞回线对制备的复合颗粒进行了表征,并考察了复合颗粒的包覆完整性。表征结果显示,液相沉积法制备的复合颗粒能够将磁核完全包覆。进一步研究了液相沉积法的原料配比、加料方式对复合颗粒的磁性和完整包覆率的影响。实验结果表明,当Fe与Ti的摩尔比为1:0.8且氟钛酸铵溶液和硼酸溶液分4次流加时,制得了高磁性的Fe_3O_4/TjO_2复合颗粒,其完整包覆率为13.4%,饱和磁化强度为22.86 emu/g。
Fe3O4/TiO2 composite particles were prepared using Fe3O4 nanoparticles as magnetic core, separately via with by sol-gel method and chemical liquid solution deposition method with reduction of ammonium fluorotitanate. Characterizations by means of XRD, TEM, hysteresis loop and degree of surface coverage illustrated that chemical liquidsolution deposition method wais efficient in covering the surface of Fe3O4 cores by with TiO：. Effects of mole ratio and feeding mode of reactants in chemical solutionliquid deposition method were further studied. Highly magnetic Fe3O4/TiOa composite particles could be obtained with coverage ratio of 13.4% and saturated magnetization of 22.86 emu/g, when n （Fe） ： n （Ti） was 1 ： 0. 8 by batchwise technique. It is preferred that the solutions containing ammonium fluotitanate and boric acid were added in four-times.
出处
《石油化工》
CAS
CSCD
北大核心
2009年第9期929-934,共6页
Petrochemical Technology
基金
高等学校博士学科点专项科研基金项目(20070056023)
石油化工催化材料与反应工程国家重点实验室开放基金项目(2008)
关键词
磁稳定床
四氧化三铁/二氧化钛催化剂
复合颗粒
饱和磁化强度
液相沉积法
magnetically stabilized bed reactor
ferroferric oxide/titania catalyst
composite particles
saturated magnetization
chemical liquid deposition
作者简介
王保国（1963-），男，河北省衡水市人，博士，教授。
联系人：李铧，电话022-27890643，电邮liwei@tju．edu．cn。
