中文摘要：

采用溶剂热法、均匀共沉淀法和溶胶-水热法分别制备出3种不同形貌的二氧化钛催化剂.采用X射线衍射仪（XRD）、X射线能谱仪（EDX）和场发射扫描电子显微镜（SEM）对催化剂的晶型结构和微观形貌进行分析.以五氯苯为模型污染物,分别在300℃、350℃、400℃条件下对3种不同形貌材料的催化活性进行评价.结果表明,3种材料的活性强弱顺序为：均匀共沉淀法所制TiO_2〉溶胶-水热法所制TiO_2〉溶剂热法所制TiO_2.均匀共沉淀法所制TiO_2在反应温度350℃、反应时间60 min的条件下对五氯苯的降解效率已经达到99.8%.通过GC-MS对五氯苯的降解产物进行分析,检测到有四氯苯、三氯苯和二氯苯等生成,表明降解反应有加氢脱氯过程发生.五氯苯加氢脱氯降解路径为：Pe CB→1,2,4,5/1,2,3,5/1,2,3,4-Te CB→1,2,4/1,2,3-TrCB→DCB.

英文摘要：

Three different morphological titania catalysts were prepared by solvothermal, coprecipitation and sol-hydrothermal methods. The materials were characterized by using X-ray diffraction（ XRD）,X-ray energy dispersive spectroscopy（ EDX） and field emission scanning electron microscopy（ FE-SEM）. The catalytic activity of titania catalysts towards pentachlorobenzene（ Pe CB） degradation was evaluated at 300 ℃,350 ℃ and 400 ℃,respectively. The results showed that the activity order was： TiO_2 prepared by co-precipitation method 〉TiO_2 prepared by solhydrothermal method 〉TiO_2 prepared by solvothermal method. The degradation efficiency of Pe CB reached 99.83% over titania catalysts prepared by co-precipitation method,at 350 ℃ for 60 min.The degradation products were determined by gas chromatograph-mass spectroscopy（ GC-MS）.Tetrachlorobenzene（ Te CB）,trichlorobenzene（ Tr CB） and dichlorobenzene（ DCB） was identified as the degradation products,indicating the occurrence of successive reductive hydrodechlorinationreactions during the degradation of Pe CB over the titania catalysts. And the major hydrodechlorination pathway was deduced to be： Pe CB→1,2,4,5 / 1,2,3,5 / 1,2,3,4-Te CB→1,2,4 / 1,2,3-Tr CB→DCB.