在Pt/TiO_2上光催化降解污水中的对氟苯甲酸  

Photocatalytic Degradation of p-fluorobenzoic Acid in Sewage over Pt/TiO_2

作　　者：谢艳招[1] 吴松辉[1] 赵林[1] 蔡聪育[1] 肖华山[1] 

机构地区：[1]福建师范大学闽南科技学院生命科学与化学系,福建泉州362332

出　　处：《分子催化》2012年第5期449-455,共7页Journal of Molecular Catalysis(China)

基　　金：福建省教育厅科技类项目(JB10209);福建师范大学闽南科技学院青年骨干教师培养基金项目(mkq201007)

摘　　要：在Pt/TiO2存在下,研究了光催化降解对氟苯甲酸的反应.考察了反应时间、溶液初始pH值以及污染物初始浓度对光催化反应的影响.结果表明,溶液的紫外吸光度值随反应时间不断下降;反应7 h时,溶液的TOC去除率达23.2%;反应0.5～2 h内,氟离子平均生成速率为3.53×10-5mol.L-1.h-1;在反应3～7 h内,氟离子平均生成速率为6.22×10-5mol.L-1.h-1.在溶液初始pH值=3.34～3.72时,氟离子生成速率最大,在碱性范围内,氟离子的生成速率为零.当C0(p-fluorobenzoic acid)<1.80×10-3mol.L-1时,光催化降解生成氟离子的速率随着对氟苯甲酸浓度的增大而增大;当C0(p-fluorobenzoic acid)>2.00×10-3mol.L-1时,光催化降解生成氟离子的速率不再随污染物浓度的变化而发生变化.探讨了可能的反应机理.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 3.53×10-5 mol·L-1·h-1 within 0.5~2 h.Average photocatalytic generation fluorine ion rate was 6.22×10-5 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.

关 键 词：光催化 降解 对氟苯甲酸 反应机理 

分 类 号：TQ034[化学工程] O643.32[理学—物理化学]