中文摘要：

采用TiO2光催化剂对受到复合污染的城市河道水进行氧化处理，发现水中的COD出现大幅升高的现象．通过对吡啶进行光催化氧化，结合紫外分光光谱分析，发现其结构发生变化，由最初不能被重铬酸钾氧化转变为可以被氧化．其COD先逐步升高后又下降．从而表明：城市复合污染水体中存在类似的有机物．进一步的实验又发现，水中这些有机物污染物在经过光催化氧化之后，可以转变为容易被微生物所利用的有机碳源，从而提高水中的碳氮比．反硝化实验证明：经过光催化氧化处理后的河道水，其总氮去除率比未经过光催化氧化的河道水提高30％以上．

英文摘要：

The COD increased greatly after the urban river water with complex pollution was oxidized under photocatalysis, the same to the water containing pyridine, which indicated there existed the similar chemicals like pyridine in the urban river water. The structure of pyridine changed after photocatalytie oxidation according to ultra violet spectrum analysis, and original pyridine could not be oxidized by potassium dichromate, but it could be oxidized after photocatalytic oxidation, and the COD increased at first, subsequently decreased during photocatalytic oxidation. Experimental results indicated that there are some recalcitrant or- ganics in urban river water with complex pollution, and these chemicals might be transferred into easy utilizable organic carbon source by microorganism after photocatalytie oxidation, which resulted in increasing carbon/nitrogen ratio. Total nitrogen removal rate increased 30 percent with photocatalytie oxidization for the river water than that without photocatalytic oxidization according to denitrification experiments.