Indirect photocatalytic reduction of arsenate to arsenite in aqueous solution with TiO_2 in the presence of hole scavengers  

作　　者：Abdus Samad Shamim Ahsan Ikki Tateishi Mai Furukawa Hideyuki Katsumata Tohru Suzuki Satoshi Kaneco 

机构地区：[1]Department of Chemistry, Jagannath University [2]Department of Earth and Atmospheric Sciences, Metropolitan State University of Denver [3]Department of Chemistry for Materials, Graduate School of Engineering, Mie University [4]Mie Global Environment Center for Education & Research, Mie University

出　　处：《Chinese Journal of Chemical Engineering》2018年第3期529-533,共5页中国化学工程学报（英文版）

摘　　要：The indirect photocatalytic reduction of arsenate to arsenite in aqueous solution with titanium dioxide(TiO_2)was investigated with various hole scavengers such as methanol, ethanol, 2-propanol, formaldehyde, acetone,formic acid and acetic acid. Although the direct photocatalytic reduction of arsenate to arsenite with TiO_2 was impossible, an indirect reduction of As(V) was possible in the presence of sacrificial electron donors to form strongly reductive radicals. The addition of ethanol was very effective for indirect photocatalytic reduction of As(V) in aqueous solution with TiO_2 photocatalyst. The indirect photocatalytic reduction rate of As(V) may be related with both the reaction rate constants of reaction of hydroxyl radicals with hole scavenger and the reactivities for the radicals M· which are produced by the reaction of ·OH with hole scavenger.The indirect photocatalytic reduction of arsenate to arsenite in aqueous solution with titanium dioxide （TiO2） was investigated with various hole scavengers such as methanol, ethanol, 2-propanol, formaldehyde, acetone, formic acid and acetic acid. Although the direct photocatalytic reduction of arsenate to arsenite with TiO2 was impossible, an indirect reduction of As（V） was possible in the presence of sacrificial electron donors to form strongly reductive radicals. The addition of ethanol was very effective for indirect photocatalytic reduction of As（V） in aqueous solution with TiO2 photocatalyst. The indirect photocatalytic reduction rate of As（V） may be related with both the reaction rate constants of reaction of hydroxyl radicals with hole scavenger and the reactivities for the radicals M· which are produced by the reaction of ·OH with hole scavenger.

关 键 词：Indirect photocatalytic reduction Arsenate Arsenite Titanium dioxide Hole scavenger 

分 类 号：O643.3[理学—物理化学] X703[理学—化学]