摘要
针对传统光催化氧化技术应用范围极大地受到水体透光性与光能在水中衰减制约的缺陷,采用液相沉积法以石英为基底制备了高透光性TiO2薄膜,并构建了一种新型的反向光催化氧化体系.以罗丹明B(RhB)为目标物质,以其降解速率反应体系光催化性能,研究了薄膜制备参数和传质效率对体系降解率的影响、正反向光催化体系性能对比、降解的主要贡献者以及薄膜的稳定性.结果表明,反向光催化体系降解10mg/L的RhB过程符合准一级动力学模型.控制沉积温度60℃沉积1.5h,并且在700℃下热处理1h,能够得到光催化性能最佳的薄膜;反向光催化体系同样产生以羟基自由基(·OH)为主的活性物种,并在降解污染物时起主要的贡献作用;相比于传统正向照射光催化体系,在透光液体层较薄时,正向照射的降解速率相对较快,反之当液体层较厚时,反向光催化则更能体现优势;此外,以最适参数制备的TiO2薄膜在反向光催化体系内循环应用时能保持稳定的光催化性能,该体系在透光性较差或光能衰减严重的水体处理领域中具备潜在的研究及应用价值.
The traditional photocatalytic oxidation technology was greatly limited by water translucency and light energy attenuation.In this study,a high transmittance TiO2film was prepared by liquid phase deposition method,and an innovative reverse photocatalytic oxidation system was constructed.The Rhodamine B(RhB)was employed as the targeted pollutant,and the degrading speed was used to evaluate the performance of reverse photocatalytic oxidation system.The effects of film preparation parameters and mass transfer efficiency on degradation were explored,while the comparisons between forward and reverse photocatalytic systems were expounded.Moreover,the major contributors for RhB degradation and the stability of TiO2film were clarified.It was demonstrated that the RhB degradation process in reverse photocatalytic system obeyed pseudo-first-order kinetics.The TiO2film with the optimum photocatalytic performance was obtained at the following parameters:deposition temperature at 60℃for 1.5h,heat treatment at 700℃for 1h.The reverse photocatalytic system produced numerous active species(e.g.·OH),which dominantly contributed to pollutant degradation.The traditional forward photocatalytic system presented significant degrading performance with thin transparent liquid layer,while the reverse photocatalytic system displayed satisfactory degrading performance with the thick transparent liquid layer.Additionally,stable photocatalytic performances were observed in the reverse photocatalytic system in the case of TiO2reuse.The proposed reverse photocatalytic system has potential research and application values in the field of water treatment with poor light transmittance.
作者
张逊之
卢金锁
张志强
杨静
庞鹤亮
ZHANG Xun-zhi;LU Jin-suo;ZHANG Zhi-qiang;YANG Jing;PANG He-liang(School of Environmental and Municipal Engineering,Xi’an University of Architecture and Technology,Shaanxi Province,Xi’an 710055,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2023年第9期4568-4577,共10页
China Environmental Science
基金
西安市青年人才托举计划(095920221346)。
关键词
反向光催化
水体透光性
薄膜制备参数
正反向效果对比
reverse photocatalysis
light transmittance of water
film preparation parameters
comparisons of forward and reverse systems
