【作者】 赵晓兰；

【导师】 张鹏；

【作者基本信息】 北京化工大学 ， 生物化工， 2003， 硕士

【摘要】 TiO2光催化技术是一项新型废水处理及净化技术,与其他传统的水处理技术相比具有降解完全、高效、价廉、稳定和可以利用太阳光等优点,因而具有良好的应用前景。本文采用悬浆体系,考察了新型氯化法制备的纳米TiO2对甲基橙的降解脱色情况。分别在高压汞灯照射和避光暗处的条件下,考察了催化剂投加量、溶液初始浓度、反应时间、反应温度对甲基橙降解脱色的影响情况并对实验条件进行了优化。适宜运行参数为:催化剂投加量为5.0 g/L～13.0 g/L,甲基橙溶液初始浓度为100 mg/L～700 mg/L,反应时间30～60 min,温度0℃～30℃。实验结果表明,该纳米TiO2对甲基橙的降解脱色受光源影响不大,对于初始浓度为100 mg/L的甲基橙溶液,在160 W高压汞灯照射下,反应30 min脱色率可达91.1%,避光暗处,脱色率可达86.9%。进一步实验研究表明,自制纳米TiO2对甲基橙具有良好的吸附性,其在避光暗处对甲基橙的脱色效果显著优于Degussa P-25型TiO2,但这并不是完全由于自制纳米TiO2对甲基橙的吸附作用而引起的;由电子自旋共振(ESR)研究表明,自制纳米TiO2在避光暗处及紫外光、可见光照射下其表面均可产生氧化能力强的·OH自由基,从而可能使甲基橙得到部分降解。更多还原

【Abstract】 TiO2 photocatalysis is emerging as a promising technology for wastewater treatment and water purification. The advantages of this technique over the traditional wastewater treatment include complete mineralizaion, high degradation efficiency, low cost, good stability, and the potential to utilize sunlight as UV source. The TiO2 nanoparticales were prepared by novel chlorination technology, and the degradation and decolorization of methyl orange (MO) in nano-TiO2 aqueous slurries was studied. The effects of light source, catalyst amount, initial concentration of solution, reaction time and temperature on the degradation rate of methyl orange were investigated under the irradiation of high pressure mercury lamp,and the same investigations were also did in the dark. The results of optimum parameters were as following: the mass concentration of nano-TiO2 5.0g/L ~13.0g/L; the initial concentration of MO 100 mg/L ~ 700 mg/L; the reaction time 30~60 min; the reaction temperature 0℃～30℃. The results indicated that light source shows a little influence on the decolorization rate of MO. <WP=6>When the initial concentration of MO was 100 mg/L, the solution color removal achieved 91.1% in 30 minutes of irradiation,and in the dark after 30 min reaction the solution color removal achieved 86.9%. Further investigations were indicated that this nano-TiO2 has good absorbability for MO, and it could decolor the MO much more efficiently than Degussa P-25 TiO2, which was not only because of its good adsorbability for MO. The ESR study justified whether the nano-TiO2 was irradiated under the ultraviolet light or in the dark, the surface of this nano-TiO2 will produce ·OH free radicals, which perhaps do some effect on the degradation of MO.更多还原