TiO2-assisted photo-catalysis degradation process of dye chemicals
The photo-catalytic degradation pathway and degradation products of methylene blue, rhodamine B, methyl orange, and malachite green in aqueous TiO2 suspension irradiated by high pressure mercury lamp by means of UV-visible absorption spectra and ion chromatography were investigated. The photo-catalysis degradation of dye solutions with charges was greatly affected by pH value owing to the electrostatic model. The photo-degradation rate of dyes anion increased with the decrease of pH value, in contrast, the photo-degradation rate of dyes cation increased with the increase of pH value. And the absorption peaks diminished with a blue shift. After illuminated for 30 minutes, a part of dye chemicals were completely mineralized and transferred into inorganic species including chloride ion, ammonium ion, nitrate ion, sulfate ion. And the addition of 100 mmmol/L H2O2 promoted the formation of inorganic species. In this study, the quantity of ammonium ion was much more than that of nitrate ion. That indicated the formation of nitrate is from ammonium. The purification rate of COD in four kinds of dye solution was 71.7%-88.7%. The decrease of COD of dyes solution implies the feasibility of the environmental application of photo-catalyzed process.
作 者： LI Fang-bai GU Guo-bang HUANG Guo-feng GU Yun-li 作者单位： LI Fang-bai(Guangdong Institute of Eco-Environment and Soil Science;College of Chemical Engineering, South Technology University)GU Guo-bang,GU Yun-li(College of Chemical Engineering, South Technology University,)
HUANG Guo-feng(Guangdong Institute of Eco-Environment and Soil Science,)
刊 名： 环境科学学报(英文版) ISTIC SCI 英文刊名： JOURNAL ENVIRONMENTAL SCIENCES 年，卷(期)： 2001 13(1) 分类号： X131 关键词：