【摘要】 以自制的β-Fe OOH中空微球为内核,十六烷基三甲基溴化铵(CTAB)为模板剂,正硅酸乙酯(TEOS)为硅源,以不同的方式添加扩孔剂癸烷(Decane)和1,3,5三甲基苯(TMB),经水解缩聚反应、焙烧和还原后得到介孔Si O2/Fe3O4中空微球。重点研究了扩孔剂的加入方式对中空微球微观形态和漆酶固定化性能的影响。结果表明,扩孔剂的加入量和加入顺序对扩孔效果产生很大影响,其中先加入癸烷和后加入1,3,5-三甲基苯的复合扩孔方式所制得介孔Si O2/Fe3O4中空微球的扩孔效果最优。当n(TMB+Decane)/n(CTAB)=2,n(TMB)/n(CTAB)=1时,介孔Si O2/Fe3O4中空微球的介孔层的厚度约50 nm,其比表面积约为855 m2·g-1,孔体积为1.23 cm3·g-1,平均孔径为5.72 nm,中空微球对漆酶的固定量达到276 mg/g;固定化漆酶活性较游离漆酶活性有一个更好的p H和温度稳定性。介孔Si O2/Fe3O4中空微球在外加磁场中可实现快速分离。更多还原

【Abstract】 Mesoporous Si O2 was coated on the home-made β-Fe OOH hollow microspheres from simultaneous polymerization of tetraethoxysilane( TEOS) in presence of a cationic surfactant( cetyltrimethylammonium bromide; CTAB) and two swelling agents,decane and 1,3,5-trimethylbenzene( TMB). The mesoporous Si O2/ Fe3O4 hollow microspheres were prepared after calcination and then reducuction. In the experiments,two swelling agents,decane and TMB were added respectively or successively to prepare microspheres with different pore sizes. Furthermore,the hollow microspheres were used as a carrier to immobilize laccase. The results reveal that compared with that of a single swelling agent,the mesoporous Si O2/ Fe3O4 hollow microspheres obtained by adding two swelling agents have better mesoporous properties. When the total pore swelling agents( CTAB) molar ratio is 2 and TMB /CTAB molar ratio is 1,the mesoporous Si O2/ Fe3O4 hollow microspheres exhibit a high surface area( 855m2· g- 1),large average pore( 5. 72 nm),high pore volume( 1. 23 cm3· g- 1). The hollowmicrospheres have larger adsorption amount and adsorption rate,and the adsorption amount of laccase are up to 276 mg / g. The activity of the immobilized laccase has a better p H and thermal stability in comparision with that of free laccase. The mesoporous Si O2/ Fe3O4 hollow microspheres can be separated in an applied magnetic field rapidly.更多还原