Pd/Ti电极上2,4,6-三氯酚还原脱氯:条件优化及降解途径

Reductive dechlorination of 2,4,6-TCP on Pd/Ti electrode: parameters optimization and degradation pathway

利用电沉积法制备了Pd/Ti电极,用于2,4,6-三氯酚(2,4,6-TCP)的电还原脱氯.采用单因素实验和响应面分析法,探讨了2,4,6-TCP脱氯试验条件;根据实验结果,拟合出了脱氯中各步骤的反应速率常数.结果表明,2,4,6-TCP初始浓度为80mg/L时,优化的脱氯参数为电流为5mA,支持电解质Na2SO4浓度为0.05mol/L,阴极电解液初始pH值为2.40.在优化条件下,2,4,6-TCP在80min内完全脱氯;2,4,6-TCP的还原脱氯符合准一级反应动力学,主要脱氯途径为2,4,6-TCP→2,6-DCP→2-CP→苯酚.

Pd loaded Ti electrode （Pd/Ti electrode） was prepared by electrodeposition method and was applied to 2,4,6-TCP dechlorination. The dechlorination parameters were investigated by means of single factor experiment and response surface analysis methods. Reaction rate constants of the possible steps in 2,4,6-TCP dechlorination were fitted out by using the experimental data. The optimized dechlorination condition of 2,4,6-TCP was obtained. i.e., current was 5mA, supporting electrolyte Na2SO4 concentration was 0.05mol/L and initial pH of catholyte was 2.40. Under the above conditions, 2,4,6-TCP with a concentration of 80mg/L could be completely dechlorinated in 80min. Dechlorination of 2,4,6-TCP followed pseudo first order kinetics. The main pathway of 2,4,6-TCP dechlorination was 2,4,6-TCP→2,6-DCP→2-CP→phenol.