纳米TiO_2的制备及其光催化降解甲基橙

Preparation of TiO_2 and Their Application inPhotocatalytic Degradation of Methyl Orange

以TiCl_4、氨水及双氧水为主要原料,通过水解法制备出纳米TiO_2光催化剂。采用SEM分析手段对制备的TiO_2颗粒进行了表征。以甲基橙溶液模拟染料废水,TiO_2为催化剂,在紫外光照条件下考察了TiO_2投加量、甲基橙初始浓度、光照时间、溶液pH值及重复利用次数对甲基橙光催化降解效率的影响。实验结果表明:TiO_2最佳的投加质量浓度为0.20 g/L;光催化反应4 h后,甲基橙的降解率可达95.67%;酸性条件有助于甲基橙的去除;TiO_2光催化剂在重复使用5次之后仍能保持较高的催化活性,甲基橙的降解率为90.35%。

The nanometer TiO2 photocatalysts was prepared by hydrolysis method with the main materials of TiCl4,ammonia and H2O2. The morphology of TiO2 particles was characterized by mean of SEM technique. Methyl orange were used to simulate dye wastewater. The effect factors of the amount of TiO2,initial concentration of methyl orange, pH value of solution, reaction time and reuse times were studied with TiO2 as catalyst under ultraviolet light. The results indicated that there is an optimal catalyst dosage of 0.2g/L; the degradation rate of methyl orange reached to 95.67% under ultraviolet light irradiation after 4h; acidic conditions contribu- ted to the removal of methyl orange ; TiO2 photocatalyst maintained a high catalytic activity after 5 times reuse and the degradation rate of methyl orange is 90.35%.