Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

作     者：Yanxiao Si Fang Zhang Chen Hong Guanghe Li Haichuan Zhang Dun Liu Yanxiao Si;Fang Zhang;Chen Hong;Guanghe Li;Haichuan Zhang;Dun Liu

作者机构：School of Environment and State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing 100084China Surface Engineering DivisionSinopec Petroleum Exploration and Production Research InstituteBeijing 100083China School of Energy and Environmental EngineeringUniversity of Science and Technology BeijingBeijing 100083China 

出 版 物：《Frontiers of Environmental Science & Engineering》 (环境科学与工程前沿（英文）)

年 卷 期：2021年第15卷第6期

页      面：211-219页

核心收录：

学科分类：08[工学] 0815[工学-水利工程] 

基　　金：supported by National Natural Science Foundation of China(Grant No.42077171) the Special Fund of State Key Joint Laboratory of Environment Simulation and Pollution Control(No.20Y02ESPCT) the Basic Foresight Project of China Petroleum and Chemical Corporation(JC-2020-KF008) the support from Young Elite Scientist Sponsorship Program by CAST(No.2015QNRC001) 

主　　题：Electrocoagulation Air cathode Arsenic Current density Energy consumption 

摘      要：Naturally occurring arsenic enrichment in groundwater poses a huge threat to human *** cathode electrocoagulation(ACEC)has recently been proposed to enhance As(Ⅲ)oxidation and lower energy *** this study,ACEC,EC/O_(2) and EC/N_(2) were evaluated with different current densities from 1 to 8 mA/cm^(2) to investigate the effect on As(Ⅲ)removal in different redox *** density had no appreciable effect on arsenic removal efficiency given the same charge in ACEC because the concentration ratio of Fe/H2O_(2) under different current densities remained ***,in EC/O_(2) and EC/N_(2),As(Ⅲ)removal was inhibited at higher current densities(4–8 mA/cm^(2)),likely because more Fe(Ⅱ)competed with As(Ⅲ)for the oxidant,leading to less effective oxidation of As(Ⅲ).In all EC systems,the$OH units generated per power consumption reached the highest value at the lowest current *** with other EC systems,the ACEC system showed lower energy consumption at all current densities due to the low energy consumption of the electrode reaction and more free radical generation.A lower current density saved more energy at the expense of time,showing the trade-off relationship between energy consumption and removal *** operation costs for As(Ⅲ)removal under optimal conditions were calculated as 0.028$/m^(3) for ACEC,0.030$/m^(3) for EC/O_(2),and 0.085$/m^(3) for EC/N_(2)