CAJ | 학술논문

以反相微乳液法和沉淀法相结合制备了核壳结构TiO2@SiO2,首次用于碳酸二甲酯与苯酚酯交换合成碳酸二苯酯反应,显示较好的催化活性.采用200°C焙烧的TiO2@SiO2,用量0.20 g,反应9h,苯酚转化率达41.8%,酯交换选择性为100%.透射电镜显示TiO2@SiO2核厚壳薄, TiO2核直径220-300 nm, SiO2壳厚度40-60 nm,具有介孔结构. TiO2@SiO2对碳酸二甲酯与苯酚酯交换反应有好的重复使用性,使用4次苯酚转化率仍保持在40%以上. TiO2与SiO2发生相互作用, Ti进入骨架形成Ti-O-Si键,骨架Ti的形成提高了TiO2@SiO2的催化性能.
이반상미유액법화침정법상결합제비료핵각결구TiO2@SiO2,수차용우탄산이갑지여분분지교환합성탄산이분지반응,현시교호적최화활성.채용200°C배소적TiO2@SiO2,용량0.20 g,반응9h,분분전화솔체41.8%,지교환선택성위100%.투사전경현시TiO2@SiO2핵후각박, TiO2핵직경220-300 nm, SiO2각후도40-60 nm,구유개공결구. TiO2@SiO2대탄산이갑지여분분지교환반응유호적중복사용성,사용4차분분전화솔잉보지재40%이상. TiO2여SiO2발생상호작용, Ti진입골가형성Ti-O-Si건,골가Ti적형성제고료TiO2@SiO2적최화성능.
Core-shell TiO2@SiO2 was prepared using a combination of reverse microemulsion and precipita-tion methods and used as a heterogeneous catalyst for the transesterification of dimethyl carbonate and phenol. TiO2@SiO2 calcined at 200 °C gave the best catalytic performance. When the amount of catalyst was 0.20 g, the phenol conversion and transesterification selectivity were 41.8% and 100%, respectively. Transmission electron microscopy was used to characterize the core-shell TiO2@SiO2 structure, and the results showed that TiO2@SiO2 is bilayer with a TiO2 core of diameter 220-300 nm and SiO2 shell of thickness 40-60 nm. The TiO2@SiO2 was reusable, and phenol conversion re-mained above 40% when the TiO2@SiO2 was used four times. The catalytic performance of TiO2@SiO2 in the transesterification of dimethyl carbonate and phenol was promoted by the for-mation of Ti-O-Si bonds.