摘要
研究了不同质量浓度TiO2、O3、H2O2光催化氧化苯甲酸的过程.结果表明：苯甲酸在光催化臭氧-过氧化氢氧化（UV/TiO2/O3/H2O2）和光催化臭氧氧化（UV/TiO2/O3）过程的去除率比单独光氧化（UV）、光催化氧化（UV/TiO2）、光催化过氧化氢氧化（UV/H2O2）过程明显增高.TiO2的最佳投加量为4.0 g/L,苯甲酸降解速度随着O3质量浓度增加而增大,低质量浓度的H2O2能促进苯甲酸氧化.动力学研究表明,苯甲酸降解过程遵循一级反应,苯甲酸在UV/TiO2/O3/H2O2作用下降解的速率常数是UV/TiO2/O3过程的1.47-6.29倍,是UV/TiO2过程的3.39-5.21倍.
Photocatalytic oxidation of benzoic acid by titania, ozoned or hydrogen peroxide of different initial concentrations were studied. The experimental results showed that combined photocatalysis with UV irradiation, ozonation and hydrogen peroxide （UV/TiOJO3/ H2O2） or combined photocatalysis with UV irradiation and ozonation （UV/TiO2/O3 ） considerably increased degradation of benzoic acid, as compared with UV irradiation alone （ UV）, or combined photocatalysis with UV irradiation （ UV/TiO2 ） , or combined hydrogen peroxide with UV irradiation （UV/H2O2）. The best usage of TiO2 was 4. 0 g/L, and the degradation speed of benzoic acid increased along with the accretion of the concentration of O3. Benzoic acid was inclined to be oxidized as H2O2 in low concentration. The kinetic study showed that the complete degradation of benzoic acid followed one - order kinetics and this depended only upon TiO2, O3 or H2O2 peroxide concentration and indicated that benzoic acid concentration did not affect the kinetics during UV, UV/TiO2, UV/H2O2, UV/ TiO2/O3 and UV/TiO2/O3/H2O2. The rate constants in the degradation of benzoic acid with UV/TiO2/O3/H2O2 were 1.47 - 6. 29 times higher than what with UV/TiO2/O3. The rate constants were 3.39 - 5.21 times higher than what with TiO2/UV.
出处
《华南师范大学学报（自然科学版）》
CAS
2007年第3期98-103,共6页
Journal of South China Normal University(Natural Science Edition)
基金
广东省科技计划资助项目(2006B36801005)
关键词
苯甲酸
光催化
二氧化钛
臭氧
过氧化氢
benzoic acid
photocatalytic
titania
ozone
hydrogen peroxide
