过渡金属离子掺杂TiO_(2)光催化降解汽油气的性能研究

Study on photocatalytic degradation of gasoline gas by transition metal ions doped TiO_(2)

采用溶胶-凝胶法制备了空白TiO_(2)及过渡金属离子(Ni、Fe、Ag、Zn)改性的光催化剂,利用FT-IR、XRD和SEM等方法对其进行表征。以汽油气为目标污染物,考察了不同工艺条件对光催化剂降解汽油气性能的影响。结果表明,与空白TiO_(2)相比,过渡金属离子改性的光催化剂晶粒尺寸明显减小,表面分散均匀且羟基数量增加,其中Zn离子改性的光催化剂对汽油气具有最佳的催化降解效果;在Zn/TiO_(2)摩尔比为0.2%、煅烧温度为550℃、汽油气初始质量浓度为14042.55 mg/m^(3)、光催化剂质量为30 g、光照强度为36 W/m^(2)的最佳降解条件下,3 h内对汽油气的降解效率达到了76.6%。

A series of photocatalysts with blank TiO_(2)and modified with transition metal ions(Ni,Fe,Ag,Zn)are prepared via the sol-gel method,and characterized by means of FTIR,XRD and SEM.Taking gasoline gas as the target pollutant,the influences of different process conditions on the photocatalytic degradation of these photocatalysts are evaluated.It is found that compared with blank TiO_(2),the transition metal ion modified photocatalysts have a significantly smaller grain size,more uniformly dispersing surface,and greater number of hydroxyl groups.Among them,Zn ion modified photocatalyst shows the best catalytic degradation effect on gasoline gas.The degradation efficiency of gasoline gas reaches 76.6%within 3 hours when the molar ratio of Zn/TiO_(2)is 0.2%,the calcination temperature is 550℃,the initial concentration of gasoline gas is 14042.55 mg·m^(-3),the dosage of photocatalyst is 30 g,and the light intensity is 36 W·m^(-2),which are the optimal degradation conditions.