XIE Yanzhao, WU Songhui, ZHAO Lin, CAI Congyu, XIAO Huashan
(Department of Chemistry and Life Sciences, Minnan Science and Technology Institute, Fujian Normal University, Quanzhou 362332, China)
Abstract: In the presence of Pt/TiO2, the photocatalytic degradation of p-fluorobenzoic acid in sewage has been studied. Effects of reaction time, initial pH and initial concentration of pollutant on photocatalytic degradation were investigated. The experiment shows that Ultraviolate Absorbance of solution continuously decreased with the reaction time. When reaction time was 7 h, TOC removal of solution was enhanced to 23.2%. Average photocatalytic generation fluorine ion rate was 3.53 x 10-5 mol • L-1 • h-1 within 0.5 ~ 2 h. Average photocatalytic generation fluorine ion rate was 6.22 x 10-5 mol • L-1 • h-1 within 3 ~ 7 h. At initial pH value of solution = 3.34 ~ 3.72, the rate of photocatalytic fluorine ion generation is maximum, in alkaline range, the rate of photocatalytic fluorine ion generation is zero. Within C0 (p-fluorobenzoic acid) < 1.80 ×10-3 mol • L-1, photocatalytic degradation generation fluorine ion rate increases with the concentration of p-fluorobenzoic acid. Within C0 (p-fluorobenzoic acid) > 2.00 × 10-3 mol • L-1, photocatalytic degradation generation fluorine ion rate is almost constant. A possible reaction mechanism was discussed.
Key words: photocatalysis; degradation; p-fluorobenzoic acid; reaction mechanism
E-mail: yanzhaoxie@sina.com
Journal of Molecular Catalysis, Vol. 26, Issue 5, 2012, 449-455
