以钛酸四丁酯为钛源，活性炭（AC）为载体，采用溶胶-凝胶法合成TiO2／AC复合体，利用TGA—DSC、SEM、XRD、DRS（漫反射光谱）及FTIR对复合体表面结构、光谱特征、晶体结构进行表征分析，并通过AAS（原子吸收分光光度计）测定铬（Ⅵ）、铜（Ⅱ）离子浓度以探讨超声-TiO2光催化还原去除率。研究表明：溶胶-凝胶法制备的TiO2／AC在290℃处由板钛矿型向锐钛矿型转变，500℃下焙烧催化活性最高；TiO2／AC复合体分散性能好、团聚尺寸低、比表面积大，其接触界面处有C-O-Ti键生成；经光催化动力学研究发现，光催化吸附还原机制符合一级动力学方程ln（c0／c）=kt及Langmuir—Hinshelwood吸附理论。对比无超声光催化，超声-光催化技术对铬（Ⅵ）、铜（Ⅱ）的还原去除率分别提高了39．32％和52．95％；催化剂循环使用3次后，超声-光催化还原铬（Ⅵ）、铜（Ⅱ）的去除率仍能达到70．61％和75．30％。
TiO2/AC composites were prepared via the sol-gel method from a carrier of activated carbon (AC) and Ti(OBu)4. Photocatalysts were characterized by TGA-DSC, SEM, XRD, diffuse reflectance spectroscopy (DRS) and FTIR. The ultrasound - TiO2 photocatalytic reduction removal rate by determination concentration of chrome (Ⅵ) and copper ( Ⅱ ) was also studied by atomic absorption spectrophotometer (AAS). The results show that TiO2/AC prepared by sol-gel method transforms from rutile into anatase at the temperature of 290 ℃ and shows the highest catalytic activity at 500 ℃. TiO2/AC composites which formed C-O-Ti between the AC bulk and TiO2 has good dispersion, low agglomeration and high surface area. The mechanism of photocatalytic reduction and adsorption follows the first order kinetics equation In(c0/c) =kt and Langmuir-Hinshelwood adsorption. Compared with the no-ultrasound, the reductive removal rate of Cr(Ⅵ ) and Cu( Ⅱ) can be improved by 39. 32 % and 52.95 % using ultrasound-photocatalytic technology. Cr(Ⅵ) and Cu( Ⅱ) removal rate is 70.61% and 75.30% even when the catalysts are recycled three times.
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