还原染料在石墨毡电极上的直接电化学还原  

Direct electrochemical reduction of vat dyes on carbon felt electrodes

作　　者：杨卓[1] 王炜[1] YANG Zhuo;WANG Wei(College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China)

机构地区：[1]东华大学化学化工与生物工程学院,上海201620

出　　处：《纺织学报》2021年第9期104-111,共8页Journal of Textile Research

摘　　要：针对还原染料的直接电化学还原存在不溶性染料和电极接触不充分而难以进行的难题,以石墨毡为工作电极,采用三电极体系,研究了还原黄3RT、还原绿FFB和还原橄榄绿B的电化学行为,并探讨了温度、电压、电流、电解质和染料浓度对直接电化学还原的影响,测试了电化学还原的电流效率和转化率。实验结果表明:还原染料可在石墨毡电极上直接进行电子得失;以石墨毡作为工作电极,可有效提高染料反应速度;提高温度可显著提高电化学反应速度;电流强度和电压过大,会增强析氢副反应,进而影响染料还原速度;在60℃,-1.0 V条件下恒压电解,染料可在10~40 min内完成还原,转化率可达90%以上,电流效率在50%~60%之间。The direct electrochemical reduction of vat dyes is difficult to carry out due to poor contact between insoluble vat dyes and the electrodes.In order to solve this problem,using graphite felt as the electrode,under a three-electrode system,the electrochemical behaviors of Vat Yellow 3RT,Vat Green FFB and Vat Olive Green B were studied,and the effects of temperature,voltage,current,electrolyte and dye concentration on direct electrochemical reduction were explored,the current efficiency and conversion rate of electrochemical reduction were also tested.The results show that vat dyes could be directly reduced into leuco.Using carbon felt cathode as electrode direct electrochemical reduction rate could be effectively improved.Electrochemical reduction rate increases significantly with the increase of temperature.At excessive level of negative potential or current,hydrogen evolution begins to occur and becomes the main rection,which affects the rate of dye reduction.Under the conditions of 60℃and-1.0 V,the vat dyes could be reduced within 10 min to 40 min,and the conversion rate could reach more than 90%,and the current efficiency is between 50%and 60%.

关 键 词：直接电化学 还原染料 石墨毡 电流效率 

分 类 号：TS193.5[轻工技术与工程—纺织化学与染整工程]