光催化降解玫瑰红的机理研究

Degradation patterns of rose red upon TiO2/UV

以玫瑰红作为研究机理的目标物，在紫外灯的照射和二氧化钛作催化剂的实验条件下，用重铬酸钾法测定化学需氧量，Apollo 9000型TOC测定仪测TOC，UV-VIS8500型紫外-可见分光光度计测定样品的色度，研究光催化降解机理。结果表明：玫瑰红染料的脱色过程与总有机碳TOC、化学需氧量COD的去除过程是不同步的。在玫瑰红的降解过程中，强氧化自由基首先进攻共轭结构．反应初期主要是脱色过程，TOC在没有很大的变化，生成了无色而又相对稳定的中间产物。反应后期是各芳烃中间产物的开环过程，最终完全降解为无机小分子。

Under the ultraviolet lamp, degradation process of rose red by TiO2 is studied. In the experiment, three testing means UV-VIS, TOC and COD are used respectively. Through UV-VIS, colorimetry can determined and the quantity of them are fixed also. TOC and COD can indicate the extent decompose of rose red distinctly. Studies illustrated that the process of decolor and the removal of TOC and COD is not simultaneous. The strong oxydic free radicals first attacked the conjugated radical in the process of basic rose red degradation. Firstly, the reaction is decolor process and basic rose red change into colourless and steady intermediate and TOC degraded little. Secondly, cyclic structure is damaged. Lastly, all intermediate is decomposed into inorganic small olecular.