废铁屑活化过硫酸盐降解偶氮染料RB5废水

采用废铁屑活化过硫酸盐(PS)降解偶氮染料废水,研究铁屑投加量、过硫酸盐浓度和初始pH值对活性黑5(RB5)降解过程的影响及动力学模型.结果表明:初始pH值为6,PS浓度为0.5 mmol·L^-1,废铁屑投加量为1 g·L^-1条件为最优的反应条件;反应50 min后,活性黑5去除率可达到90.22%,180 min后去除率可达到96.97%,反应后溶液中总铁的溶出量为97.32 mg·L^-1;RB5降解后,产生的副产物苯胺的质量浓度为0.13 mg·L^-1,反应后出水的pH值从初始的6变为4.01,废铁屑/PS体系降解RB5的降解动力学符合一级动力学反应;采用废铁屑活化过硫酸盐工艺降解偶氮染料废水具有反应速度快,不需调整初始pH值、运行成本低等优势.

Degradation of Azo Dye RB5 Using Persulfate Activated With Iron Chips

This study revealed potassium persulfate(PS)activated by waste ferrous scurf to degrade Reactive Black 5(RB5). Three variables(i. e., pH, persulfate concentration, and ferrous concentration)were defined as significant factors for decolorization to investigate the influence on the degradation and dynamics. The results showed that the optimal efficiency could be achieved under the conditions of: pH=6, persulfate concentration=0.5 mmol·L^-1, and ferrous concentration=1 g ·L^-1. When the reaction time increasing from 50 min to 180 min, the decolorization rate of RB5 increased from 90.22% to 96.97% with the Fe release of 97.32 mg·L^-1. After 180 min reaction, aniline, as the main intermediates of RB5 degradation, was accumulated to 0.13 mg·L^-1, and the pH changed from 6 to 4.01. In addition, the rate constant fitted the first-order kinetics. Overall, the ferrous scurf activated PS system has the advantages of rapid reaction rate, less pH adjust and low cost.