二氧化钛紫外光(UV/TiO_(2))降解2,4,6-三氯酚的多因素影响

Multi-Factor Influence of UV/TiO_(2) on Degradation of 2,4,6-TCP

采用UV/TiO_(2)高级氧化技术对2,4,6-三氯酚(2,4,6-TCP)进行降解试验,结果表明,UV/TiO_(2)高级氧化工艺能有效降解2,4,6-TCP,且符合准一级动力学模型,相关系数均在0.96以上。TiO_(2)投加量、2,4,6-TCP初始质量浓度、紫外光照强度、pH、阴离子对UV/TiO_(2)降解2,4,6-TCP速率均有影响。试验结果显示:TiO_(2)投加量为500 mg/L时,2,4,6-TCP的去除率为最佳;随着2,4,6-TCP初始质量浓度增加,2,4,6-TCP的降解速率降低;在酸性及弱碱性(pH值≤8.96)环境中,酸性条件有利于降解2,4,6-TCP,而在强碱性(pH值≥8.96)环境中,pH的升高有利于降解反应的进行;随着紫外光照强度增加,2,4,6-TCP的降解速率增加;阴离子对反应速率的影响为无阴离子>SO_(2)>NO_(2)>CO_(2)>Cl^(-)。

UV/TiO_(2)advanced oxidation process was used to degrade 2,4,6-trichlorophenol(2,4,6-TCP). Results showed that UV/TiO_(2)advanced oxidation technology can degrade 2,4,6-TCP effectively and accord with quasi-first order kinetic model. Correlation coefficient was above 0.96. Degradation rate of 2,4,6-TCP of UV/TiO_(2)was affected by the amount of TiO_(2), initial mass concentration of 2,4,6-TCP, UV light intensity, pH value and anions. Results showed that the removal rate of 2,4, 6-TCP was the best when TiO_(2)dosage was 500 mg/L. Initial mass concentration of 2,4,6-TCP increases, and degradation rate decreases. In acidic and weakly alkaline(pH value≤8.96) environments, acidic conditions were conducive to the degradation of 2,4,6-TCP, while in strongly alkaline(pH value≥8.96) environments, the increase of pH value was conducive to degradation reaction. Degradation rate of 2,4,6-TCP increases with the increase of ultraviolet light intensity. Influence of anions on reaction rate was as follows absent of anions>SO_(2)>NO_(2)>CO_(2)>Cl^(-).