【作者】 闫晔；

【导师】 张鹏；

【作者基本信息】 北京化工大学 ， 生物化工， 2008， 硕士

【摘要】 以纳米TiO₂为催化剂的光催化氧化技术是一种新型的废水处理技术,具有高效、无二次污染、成本低、可以利用太阳光等优点,因而受到广泛关注。本文利用纳米TiO₂催化剂对模拟苯酚废水进行光催化处理,研究了光源种类、pH值、苯酚初始浓度、催化剂的用量等外部因素对P-25纳米TiO₂催化剂光催化降解过程的影响,对比研究了自制TiO₂催化剂的降解效果和回收再利用的效果;同时研究了TiO₂/UV与活性炭颗粒、H₂O₂、Fenton试剂等不同体系的协同效应;初步探讨了苯酚催化降解的机理和降解途径。实验表明:在TiO_/UV悬浮体系中,紫光外照射4hr,催化剂用量为1.5g/L、pH=4时,苯酚降解率可达35.8%;苯酚降解率随初始浓度的升高而降低,光催化降解过程符合一级反应动力学;自制纳米TiO₂催化剂在紫外光下有较好的降解效果,在暗处和自然光照射下也有一定的催化效果。根据正交试验分析,自制纳米TiO₂催化剂活性影响因素的大小为光源种类＞初始浓度＞溶液pH值＞反应方式。该催化剂回收后经活化可反复使用,是应用前景广泛的绿色环保光催化剂。在TiO₂/UV悬浮体系内加入0.25ml 30%H₂O₂,苯酚降解率可提高到56%;加入Fenton试剂（0.05ml 30%H₂O₂溶液和0.25m10.1MFeSO₄溶液）15min降解率可达到90%以上,存在协同效应;添加活性炭后的协同效应不明显。结果说明光催化剂氧化与其它技术的合理组合可以有效提高苯酚的去除效果,为纳米TiO₂催化剂实际应用提供了实验依据。更多还原

【Abstract】 Photocatalytic degradation of organic contaminant is a promising technology of wastewater treatment. In this field, TiO₂ is used as photocatalyst extensively for its high photoactivity, none secondary pollution caused and the potential utilization of solar energy.The thesis was focused on treating the Phenol with the nano-TiO₂ photocatalyst in the simulated wastewater. The influencing factors were studied including different light sources , initial concentration of Phenol, pH of solution and the amount of nano-TiO₂ added .The comparison of degradation effect was made between the P25 TiO₂ and self-preparation TiO₂ catalyst. Reused effect of self-preparation TiO₂ catalyst was studied. The synergistic effect was concerned to TiO₂ with other materials. The elementary kinetics discipline was discussed in photocatalysis of Phenol and the pathway of degradation of the Phenol was predicted.Results indicated that: Photodegradation efficiency of Phenol is 35.8% in TiO₂- Phenol suspended system in 4 hr under the following conditions: Phenol concentration 100mg/L with 1.5g/L of P-25TiO₂ at pH=4 and with 16W ultra-violet sterilization lamp. The degradation rate decreased with the increase of initial concentration of Phenol. The research indicated that the self-preparation nano-TiO₂ exhibited high photocatalytic action under ultraviolet radiation. It also showed some photocatalytic effect under nature light source and in the dark. The nano-TiO₂ could be reusable by activation which helped it to become a widely used green environmental photocatalyst. The degradation rate of Phenol can be higher to 56% when 30%H₂O₂ was added into the TiO₂ /UV suspended system. The degradation rate of Phenol can be higher than 90% in 15 minutes when Fenton reagent was added. The effective degradation was achieved by the synergistic effect of TiO₂/UV and H₂O₂ or Fenton agent. But the synergism is not evident between TiO₂ /UV and active carbon granule. Photocatalytic oxidation combines with other proper technology is regarded as a future advanced oxidation technology in environmental protection.更多还原