锐态型纳米TiO_2光催化处理含镉废水的研究

采用溶胶-凝胶法制备锐态型纳米TiO2,用XRD、SEM对粉体进行表征。在紫外光的作用下将自制纳米TiO2光催化处理废水中的Cd2+。考察反应时间、pH值、废水负荷、催化剂用量等因素对去除率的影响。实验结果表明:纳米TiO2光催化处理含镉废水的去除率高,含镉废水pH值、废水负荷、纳米二氧化钛浓度以及反应时间等因素影响含镉废水去除率。在优化的处理条件中:废水镉浓度为30mg/L,纳米TiO2投加量为3mg/L,含镉废水的pH为10,反应时间为2.5h,废水中镉的去除率可达99.52%。

Study on Anatase Nanometer TiO2 Applicated in Treating Wastewater Containing Cd2+

The anatase nano-titanium dioxide was prepared using optimization of sol-gel method and was characterized by XRD and SEM.Photocatalytic treatment of the wastewater containing Cd^2＋ ions with the UV excitation by nanometer TiO2 was investigated.The removal efficiency of Cd^2＋ was affected by reaction time,pH value,initial concentration of Cd^2＋,amount of catalyst.The experimental results show that nanometer TiO2 can be used as photocatalyst to remove Cd^2＋ from the wastewater effectively with the UV excitation.The wastewater pH value,the initial concentration of Cd^2＋,the amount of catalyst,the reaction time and other factors affect the efficiency of photocatalytic treatment significantly.The best experimental conditions for photocatalytic treatment of wastewater containing Cd^2＋ ions are as follows,when the concentration of Cd^2＋ in the wastewater is 30mg/L,amount of TiO2 is 3mg/L,pH value is 10 and the reaction time is 2.5h,the removal rate of Cd^2＋is up to 99.52%.