中文摘要：

用XRD、FTIR及TG-DSC等手段对磁选后的天然钒钛磁铁矿进行结构表征,然后在酸性条件下,探讨天然钒钛磁铁矿非均相Fenton法催化降解酸性橙Ⅱ的性能。结果表明：磁选后的天然磁铁矿主要以钛磁铁矿为主,同时含有少量的钛铁矿和绿泥石。降解实验结果表明,天然钒钛磁铁矿催化降解酸性橙Ⅱ的能力明显强于人工合成的单相磁铁矿,并随着钛磁铁矿含量的增加而增强。降解过程以异相Fenton反应为主,动力学曲线符合准一级方程。反应开始210min后,天然钒钛磁铁矿对酸性橙Ⅱ的矿化率约为30%。在降解过程中,苯环和萘环逐步断裂。

英文摘要：

The natural magnetites after magnetic separation were characterized with XRD,polarizing microscope,FTIR and TG-DSC.The catalytic activity of natural vanadium-titanium magnetite in the degradation of acid orange II throuth non-homogeneous Fenton reaction was also studied in the acid condition.The results showed that the natural samples mainly contained titanomagnetite,with a small amount of ilmenite and chlorite.The degradation experiment revealed that the catalytic activity of natural vanadium-titanium magnetite in the degradation of acid orange II was stronger than that of synthesized non-doped magnetite（Fe3O4）.The improvement of the catalytic efficiency of the natural samples strongly depended on the content of titanomagnetite.The present study showed that the degradation process was dominated by heterogeneous Fenton reaction,complying with pseudo-first-order rate law.210 min after the reaction starting,percentage of the mineralization of Acid Orange II was about 30%.The phenyl and naphthyl in Acid Orange II were gradually broken during the degradation process.