改性PTFE纤维铁配合物催化不同结构偶氮染料的氧化降解反应

Degradation of azo dyes with different structures by grafted polytetrafluoroethylene fiber Fe complex

为研究不同结构偶氮染料的光催化降解行为和规律,制备改性聚四氟乙烯(PTFE)纤维铁配合物作为非均相Fenton反应催化剂应用于9种不同结构水溶性阴离子偶氮染料氧化降解反应中,分别考察了催化剂中铁离子含量、铜离子的引入、水溶液中氯化钠的存在和pH值对不同结构水溶性偶氮染料氧化降解反应的影响.结果表明:催化剂中铁离子含量的提高和铜离子的引入均有利于偶氮染料氧化降解性能的提高,且它们的脱色率与其MW/S值(分子质量与磺酸基数目比值)之间存在着负相关性;氯化钠存在或碱性环境使偶氮染料尤其是具有较多磺酸基的活性和直接染料的氧化降解反应都受到抑制,并且导致它们的脱色率与其MW/S值之间的关系发生了变化.

The grafted polytetrafluoroethylene fiber Fe complex was first prepared and then used as the heterogeneous Fenton reaction catalysts for the oxidative degradation of 9 typical water-soluble anionic azo dyes with different structures to study their photodegradation properties in water. A few factors affecting the photodegradation of these dyes, such as the ferric ion content loading on caalyst, incorporation of Cn ions, in the presence of sodium chloride and pH of the solution were investigated. The results indicated that increasing Fe content of catalyst or incorporation of Cu ions could promote the dye degradation, and the deeolorization percentage of the dyes showed a negative relation with their MW/S. Sodium chloride or alkaline environment had a significant inhibition effeet on the degradation of dyes, especially reactive dyes and direct dyes which with more sulphonate groups, and changed the relationship between deeolorization percentage of the dyes and their MW/S.