【作者】 曹跟华；

【导师】 任宝山； 罗人明；

【作者基本信息】 河北工业大学 ， 化学工艺， 2003， 硕士

【摘要】 光催化氧化技术是指利用半导体光催化剂如TiO₂、ZnO等，通过光催化氧化作用氧化降解水和空气中有机污染物的技术。它具有高效、节能、广普安全、无二次污染的特点，成为一种新兴的高级化学氧化技术，有着广阔的应用前景。 本论文在分析国内外光催化反应器工作原理及结构特点的基础上，自行研制了内循环光催化反应器，并用此反应器研究甲基橙和玫瑰红染料模拟废水的处理，取得了很好的去除效果。在最佳实验条件下，甲基橙降解率为92.1％，玫瑰红则完全降解。实验表明，光催化反应器内外径比、催化剂状态、供氧速率、气—液—固传质、废水色度等因素对光催化降解效率影响显著。催化剂处于悬浮态时甲基橙的降解率要高于其处于负载时的降解率。最佳实验条件为：内外径比9/15，适宜的气体流速0.015m/s。鼓风供氧对反应有明显的促进作用，若不鼓氧，降解反应非常缓慢。动力学研究表明，在鼓风条件下，甲基橙光催化降解可近似看作是一级反应，论文计算了不同条件下的表观动力学常数，并初步建立了动力学模型。 本论文利用总有机碳（TOC）测定仪、紫外—可见分光光度计、化学需氧量（COD）等多种分析方法，确定玫瑰红的光催化氧化降解过程，进而探索了光降解的机理。研究表明，强氧化自由基首先进攻共轭基团。玫瑰红染料的脱色过程与总有机碳TOC的去除过程是不同步的。反应初期主要是脱色过程，反应后期是各中间产物的完全降解。TOC在初期没有很大的变化，说明生成了无色而又相对稳定的中间产物。通过对甲基橙和玫瑰红降解过程的分析，发现玫瑰红具有较高的反应活性，能够很快的对光解作出明确的反应，而甲基橙在光反应初期表现出阻抑作用。更多还原

【Abstract】 Photocatalytic oxidation is a technique for removal of pollutants from aqueous and ail-streams by semiconductors such as TiO2, ZnO. Its has become a new advanced oxidation processes (AOPs) and has widely used because of high- efficiency, low- power, wide-safety. Therefore, it is important that photocatalytic oxidation be developed.According to work principle and configuration of the photocatalytic reactor, inner-circulation photoreactor was made in this article. The photocatalytic degradation of methyl orange with titanium dioxide in self-made inner-circulation photoreactor was investigated and got a successful removal in this work. In the best performance, color removal was 92.1% and basic rose red was decomposed completely. Experiment indicated that suspended TiO2 has higher radio than supported TiO2. The parameters such as the ratio between inter-diameter and outer-diameter, state of titanium dioxide, good transmission in G-L-S three phase systems, initial chroma of waste water has great influence in the photoreaction. The best condition is: ratio between inter-diameter and outer-diameter is 9/15, air bubbling flow is 0.015m/s. Without air bubbling, the degradation is very slow. Air bubbling can accelerate the decomposition reaction notable. Through the analysis of the experiment data, the apparent reaction of heterogeneous photocatalytic reaction of methyl orange in water under air bubbling is known to be one. The apparent kinetic in different conditions constants were calculated and the preliminary kinetic model was built.Through the analysis of Total Organic Carbon (TOC), UV-VIS and Chemical Oxygen Demand (COD), the process of basic rose red degradation was determined and mechanism of photocatalysis was deduced. Studies illustrated that the strong oxydic free radicals attacked the conjugated radical first. The process of decolor and the removal of TOC is not simultaneous. Firstly, the reaction is decolor process. Secondly, intermediate is decomposed. Basic rose red changed into colourless and steady intermediate because TOC degraded little in initial stages. Through the analysis of the degradation process of methyl orange and Basic Rose Red, Basic Rose Red was much vivacious than methyl range. Basic Rose Red can make specific reaction.Otherwise methyl orange has retardarce in initial stages.更多还原