偶氮染料光助还原脱色反应机理的研究  

Study on the photo-assistant reducing decoloration mechanism of azo dyes

作　　者：董永春[1] 李春辉[1] 张宝华[1] 

机构地区：[1]天津工业大学材料科学与化学工程学院,天津300160

出　　处：《纺织学报》2006年第2期5-8,16,共5页Journal of Textile Research

基　　金：天津市自然科学基金资助项目(043605911);天津市高校科技发展基金资助项目(2003-1007)

摘　　要：选择7种水溶性阴离子偶氮染料为目标染料,使用基于硼氢化钾/重亚硫酸钠体系的还原脱色剂对其进行光助还原脱色反应,并以紫外可见光谱法对其反应机理进行了分析,考察了还原脱色剂浓度和光辐射强度对其反应机理的影响。并借助联苯胺类直接染料,通过其还原生成物氧化后的光谱测定,表征了染料还原反应生成的联苯胺。结果表明,在此类还原脱色剂作用下,偶氮染料首先被还原为中间产物氢化偶氮,并且还原脱色剂浓度的提高和光辐射强度的增加都能促进偶氮染料的还原脱色反应。还原反应生成联苯胺的鉴定证实反应体系中偶氮染料能够被进一步还原为芳香胺。The decoloration of 7 anionic water-soluble azo dyes in aqueous solutions was carried out by using photo-assislant sodium bisulfite/ potassium borohydride system based reductant, and the reaction mechanism was analyzed through UV-Vis spectrum. The effect of concentration of reductant and irradiation strength on decoloration of dyes was investigated. In addition, rapid colorimetric determination of benzidine compounds released from photo-assistant reduction of selected direct dyes was also conducted. The results indicate that photo-assistant reduction of azo dyes may first lead to formation of hydride azo compounds, and higher concentration of the reductant and enhanced irradiation improve the decoloration of azo dyes. The confirmation of benzidine compounds in decolorized solutions demonstrates that further reduction of azo dyes with sodium bisulfite/potassium borohydfide system based reducing agent will produce aromatic amine.

关 键 词：偶氮染料 还原脱色 机理 紫外可见光谱 

分 类 号：X131[环境科学与工程—环境科学]