KBrO3协同载贵金属TiO2光催化降解阿莫西林

Synergistic photocatalytic degradation of amoxicillin by precious metal supported TiO2 with KBrO3

摘要:

为提高二氧化钛光催化去除阿莫西林的效率,利用光沉积法制备了载贵金属TiO₂催化剂 (M／TiO₂,M为Ru、Rh、Pd、Ag、Ir、Pt或Au),研究紫外光(365 nm)下KBrO₃协同M／TiO₂光催化降解阿莫西林的活性,并以KBrO₃协同Rh／TiO₂研究实验条件对催化活性的影响．结果表明：M／TiO₂光催化降解阿莫西林的催化活性与贵金属的功函数密切相关;KBrO₃对不同M／TiO₂光催化降解阿莫西林的反应均具有很好的协同效果;在Rh载量为0.1％(质量分数)、催化剂质量浓度为0.15 g／L、KBrO₃浓度为0.5 mmol／L、溶液pH为5的条件下,20 mg／L的阿莫西林溶液90 min光催化降解率达100％,且该反应符合一级反应动力学模型．

Abstract:

To improve the photocatalytic efficiency of TiO₂ for amoxicillin removal, a series of precious metals catalysts (M／TiO₂, M=Ru, Rh, Pd, Ag, Ir, Pt or Au) were prepared by light deposition method. The synergistic photocatalytic activity of M／TiO₂ with KBrO₃ for degradation of amoxicillin (20 mg／L) in aqueous solution was researched under UV light (365 nm). The effects of metal loading, catalyst concentration, KBrO₃ concentration and pH on the photocatalytic activity of Rh／TiO₂ with KBrO₃ were explored. The results show that the photocatalytic activity of M／TiO₂ is closely related to its work function and KBrO_3has a greatly synergistic role on M／TiO₂. Under the conditions of 0.1％ Rh loading, Rh／TiO₂ concentration of 0.15 g／L, KBrO₃ concentration of 0.5 mmol／L and reaction liquid pH value at 5, the amoxicillin can be degradated completely within 90 min. Furthermore, the results of kinetic study show that the degradation reaction can be expressed by the first-order reaction kinetic model.