Photocatalytic Degradation of Chlorophenols in Pulp Bleaching Effluents
In pulp bleaching effluents the absorbable organic halide compounds(AOX)are the major contributors to mutagenicity and bioaccumulation,because of their hydrophobicity and the ability to penetrate cell membranes.Photocatalysis has been accepted as a promising alternative to the conventional methods,in respect that most pollutants can be completely mineralized to carbon dioxide in the presence of UV and visible illumination with suitable catalysis.This review presented the photocatalytic degradation of chlorophenols under UV and visible lights irradiation and discussed the tendency of photocatalytic development.It addressed the various possibilities to couple heterogeneous photocatalysis with other technologies to photodegrade chlorophenols in pulp bleaching effluents.When the coupling is with ultrasonic,microwave,electricity,and the combination affect the photocatalytic mechanisms thus improving the efficiency of the photocatalytic process.Mechanisms of photolycatalytic,secondary reactions for mono-,di-,tri-,tetra-and pentachlorophenol are proposed.The pathways for intermediate reactions are also presented.Visible light photocatalytic detoxification of water is technologically and environmentally attractive as it can be applied on a very large scale for industrial or domestic wastewater treatment or purification.Therefore,visible light photodegradation of chlorophenols are analyzed in the points of efficiency,influencing factors,intermediates and reaction mechanisms.In conclusion,photocatalytic degradation of chlorophenols appears to be the most promising tool for developing real applications of pulp bleaching effluents and other decontamination processes.
chlorophenols UV visible lights photocatalysis ultrasonic microwave electricity
BIN YANG YONGLI CHEN GUONING CHEN SHUANGFEI WANG
Guangxi University,Nanning,530004,China
国际会议
第二届国际造纸与环境学术会议(The Second International Papermaking & Environment Conference)
天津
英文
1129-1134
2008-05-14（万方平台首次上网日期，不代表论文的发表时间）