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本论文研究以蛇纹石尾矿酸浸渣(以下简称蛇纹石尾矿渣)为原料,采用煅烧工艺制备负载纳米TiO2的矿物载体；以TiCl4为前驱体,采用水解沉淀法制备纳米TiO2/蛇纹石尾矿渣复合材料。通过正交实验确定了四个主要因素对复合材料光催化性能的影响,筛选出较优的制备工艺条件；通过单因素实验分析了工艺因素对材料性能的影响。应用XRD、EDX (EDS)、SEM、FT-IR、TEM、XPS仪器分析技术对复合材料结构与性能进行了表征。结果表明,制备的复合材料中锐钛矿晶型TiO2占89.8wt%,TiO2晶粒度为10～30nm左右；TiO2与蛇纹石尾矿渣载体之间主要以Si-O-Ti化学键结合,纳米TiO2与基体融合程度完好,载体颗粒表面和内部点位均有纳米TiO2负载,且负载均匀性较好；蛇纹石尾矿渣载体颗粒负载的TiO2渗入载体材料表面以下一定深度,与SiO2形成混合的负载界面层,厚度大约为500～800nm；复合材料BET单点比表面积为120.4 m2/g,吸附平均孔径为15.1nm,单点吸附总孔体积为0.183 cm3/g,具备较大的比表面积和孔体积。在表征和分析基础上探讨了复合粉体材料的制备机理。应用实验表明,该材料对含酚废水和含Cr(Ⅵ)废水紫外光催化降解效果较好,降解率可达90%以上,使用过的催化复合材料经回收处理后可多次重复使用,是一种高效、低耗的新型环保功能材料。Serpentine mine acid leaching tailings (hereinafter referred to "serpentine tailings" as a short term) was calcined as the mineral substrate to load nanometer titanium dioxide.The nano TiO2/serpentine tailings composite material was prepared by means of hydrolysis-depositing, in which process TiCl4 was used as the precursor. Four factors were identified as major factors on photocatalysis properties of composite material by orthogonal experiments; the optimal preparation conditions were selected. Impact of process technology factors on the material properties were analyzed by single factor experiment method as well. XRD, EDX (EDS), SEM, FT-IR, TEM, XPS analysis instruments and measures were applied to characterize structure and properties of the composite material. The results showed that anatase TiO2 was in accounting for 89.8wt% in the whole product, grain size was about 10～30 nm. TiO2 mainly combined with the serpentine tailings substrate by Si-O-Ti bonds, serpentine tailings particle surface and internal points are coated by nano-Ti02 evenly. TiO2 particles are dispersive into a certain depth below the surface of serpentine tailings particles, forming a mixed coating interface with the SiO2 layer, of which the thickness was about 500～800 nm. Composite material possessed larger surface area and amounts of pore volume. Its volume and surface area parameters were listed as below:single point