采用循环伏安法和紫外光谱法对有机物的光催化降解进行机理研究和在线监测.以标准光催化剂DegussaP25在紫外光照射下催化降解4-氯苯酚，发现在降解过程中至少有两对氧化还原中间产物:对苯二酚-苯醌和羟基氢醌-羟基苯醌.由4-氯苯酚及中间产物的电极响应，可以观测到它们在光催化降解过程中的含量变化，从而对整个过程实现在线监测，并由此全面了解光催化反应机理.从不同反应时间后测得的紫外光谱可以看到，苯环特征峰逐渐消失.这表明4-氯苯酚的苯环逐渐被打开，直至被彻底降解.
On-line monitoring in photocatalytic degradation process oforganic compound 4-chlorophenol (4-CP) w as carrie d out by using cyclic voltammetry and UV-Vis spectrometry. The result showed th at the degradation process undertook at least a two-route mechanism to the comp lete mineralization: through redox pairs of benzoquinone(BQ) and hydrobenzoquinone(HQ ) and of hydroxybenzoquinone(HBQ) and hydroxyhydrobenzoquinone(HHQ). UV-Vis spe ctra taken at different time showed the breakage of benzene ring and the complet e mineralization. The electroanalysis was proved to be a proper technique for on -line monitoring as it could detect simultaneously both initial reactants and intermed iates, and thus it is suitable for on-line monitoring and complementary for mec hanism study.
参考文献
| [1] | 沈伟韧,赵文宽,贺飞,方佑龄.TiO2光催化反应及其在废水处理中的应用[J].化学进展,1998(04):349-361. |
| [2] | Hagfeldt A;Grtzel M .[J].Chemical Reviews,1995,95(01):49. |
| [3] | Al-Sayyed G;D'Oliveira J C;Pichat P .[J].Journal of Photochemistry and Photobiology A:Chemistry,1991,58(01):99. |
| [4] | Theurich J;Lindner M;Bagnemann D W .[J].Langmuir,1996,12(26):6368. |
| [5] | Stafford U.;Kamat PV.;Gray KA. .PHOTOCATALYTIC DEGRADATION OF 4-CHLOROPHENOL - THE EFFECTS OF VARYING TIO2 CONCENTRATION AND LIGHT WAVELENGTH[J].Journal of Catalysis,1997(1):25-32. |
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