上流式生物电化学系统深化处理2-氯硝基苯废水

构建了多组上流式生物电化学反应系统(up-flow bio-electrochemical system,简称UBES),研究了UBES降解2-氯硝基苯(2-CNB)废水的特性,探究了2-CNB在UBES中降解的影响因素和降解途径.实验结果表明:在一定范围内增大外加电压,2-CNB在UBES系统中降解速率与电压值呈正相关,当外加电压超过某一范围时,2-CNB降解速率下降.中性条件下,当2-CNB初始浓度为20 mg·L~(-1),外加电压为1.4 V反应30 h后,2-CNB的降解率达到99.61%;采用HPLC、HPLC/MS、HPLC/MS/MS及IC技术,分析了2-CNB降解24 h的中间产物,结果表明:2-CNB在降解过程中将产生苯胺、2-氯苯酚、苯二酚、2-氯苯胺、2-氯亚硝基苯、2-氯羟基苯胺、正己酸、丁二酸等中间产物,部分Cl元素和N元素分别转化为Cl~-和NO~-_3.2-CNB在UBES系统中降解包含阴极还原、阳极氧化两种降解途径.

Enhanced treatment of 2-chloronitrobenzene wastewater by up-flow bio-electrochemical system

Multiple groups of up-flow bio-electrochemical system(abbreviation UBES) have been constructed, the characters of 2-CNB waste water degradation by UBES, the influential factor of the degradation process, as well as 2-CNB degradation patheay in UBES have been studied. The results show that 2-CNB degradation rate in the system was positively correlated with the voltage value in a certain range, When the external voltage exceeded a certain limit, the rate of degradation reduced promptly. Under the neutral situation, when the initial concentration of 2-CNB was 20 mg·L^-1, external voltage was 1.4 V and the react time was 30 h, the removal rate of 2-CNB reached 99.61%. The intermediates after degraded for 24 hours were analized by HPLC/MS and HPLC/MS/MS and IC, which showed that aniline, 2-chlorophenol, catechol, 2-chloroaniline, 2-chloro-nitrobenzene, 2-chloro-hydroxy aniline, n-adipic acid, succinic acid were produced in the course of decomposition and part of Cl and N turned into Cl^- and NO₃^-. 2-CNB has two decomposition pathways in the system cathode reduction and anodic oxidation.