摘要
采用非离子型Ｗ／Ｏ微乳液中水核作为“微反应器”制备水合ＴｉＯ２，在不同温度煅烧得到形态不同的ＴｉＯ２超细粒子；研究ＴｉＯ２粒子作为光催化剂降解含酚溶液的催化活性。结果表明，前驱体煅烧温度对粒子光催化活性有明显影响，煅烧温度低、粒径小、比表面积大的粒子催化活性强；酚去除率随ＴｉＯ２浓度升高而升高，但存在最大值；通入适量氧气有助于酚的去除，但通氧速率过大酚去除率反而下降；用酚氧离子在ＴｉＯ２表面吸附机理解释ｐＨ值对光催化反应的影响。
Ultrafine TiO_2 particles were synthesized in nonionic Triton X100/nhexanol/cyclohexane/water water in oil (W/O) microemulsion by mixing two separately prepared microemulsions containing TiCl_4 and NH_3·H_2O respectively. In this process, the aqueous cores of the microemulsion were used as a microreactors for the precipitation of precursor titanium hydroxide. The hydroxide particles prepared were calcinated at different temperatures to form ultrafine TiO_2 particles. The photocatalytic destruction of phenol in aerated solution with suspensions of prepared and commercial titania particles were investigated. The photoactivity of microemulsionmediated ultrafine anatase TiO_2 particles is higher than that of all used commercial particles. The experimental results indicate that there is an optimum value for the titania content. Sufficient O_2 supply is needed, but a too high gas flow rate induces large bubbles that eliminate the gas residence time and the gas/liquid contact interface. The pH value of the phenol solutions has a complex effect on the photoactivity of the particles. A mechanism of the phenoxide ions being adsorbed on the titania surface were used to account for this effect.
出处
《华东理工大学学报（自然科学版）》
CAS
CSCD
北大核心
1998年第3期291-297,共7页
Journal of East China University of Science and Technology
关键词
超细粒子
二氧化钛
苯酚
光催化
废水处理
ultrafine particles
titania
W/O microemulsion
phenol
photocatalysis
