摘要
以电解锰行业清洁化与资源化发展为目标,探究了电渗析工艺中单价选择性阳离子交换膜(CSO)对电解锰废水中的阳离子Mn^(2+)、NH_(4)^(+)及Mg^(2+)选择性分离的效果、规律及影响因素.结果表明选择性系数P_(NH_(4)^(+)^(Mn)^(2+))远小于1,即CSO膜能轻易实现NH_(4)^(+)和Mn^(2+)的选择性分离,保障任意时刻NH_(4)^(+)迁移量均远高于Mn^(2+).由于边界层内的离子扩散差异,Mn^(2+)的选择透过性随电流密度与离子总浓度增大而降低,且电流密度的影响更为显著.在Mn^(2+)、NH_(4)^(+)和Mg^(2+)三离子体系中,迁移顺序为NH_(4)^(+)>Mn^(2+)>Mg^(2+),与离子水和作用能的差异一致,且电压变化曲线呈现出S型变化规律,可用于评价电渗析过程中单价离子的迁移进程.
Towards cleaner production and resource utilization in electrolytic manganese industry,this work investigated the influence of monovalent selective cation exchange membrane(CSO)on separation of Mn^(2+),NH_(4)^(+) and Mg^(2+)via electrodialysis(ED).P_(NH_(4)^(+)^(Mn)^(2+)) was found far less than 1,in line with the fact that CSO membrane realized the facile separation of NH_(4)^(+) and Mn^(2+),maintained a much higher migration amount of NH_(4)^(+) than its counterpart during the desalination period.Due to the difference of ion diffusivity in the boundary layer,the perm-selectivity of Mn^(2+)over NH_(4)^(+) decreased with the increase of current density and total ion concentration,with the former factor more significant.In the Mn^(2+),NH_(4)^(+) and Mg^(2+)tertiary system,the order of sequence for the migration rate was NH_(4)^(+) >Mn^(2+)>Mg^(2+),in consistence with the level of their corresponding ion hydration energy.Furthermore,the voltage variation which exhibted an S-shaped could be used to evaluate the migration extent of monovalent during ED process.
作者
何飞阳
向文毓
陈舒琦
胡晓宇
韩乐
HE Fei-yang;XIANG Wen-yu;CHEN Shu-qi;HU Xiao-yu;HAN Le(Key Laboratory of Eco-environment of Three Gorges Reservoir Area,Ministry of Education,College of Environment and Ecology,Chongqing University,400045,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2022年第3期1202-1208,共7页
China Environmental Science
基金
留学人员回国创业创新支持计划重点项目(CX2018004)
中央高校科研项目(2020CDJQY-A015)
重庆大学本研联合项目(20190007)。
关键词
电解锰废水
锰
电渗析
选择性分离
选择透过性
electrolytic manganese wastewater
manganese
electrodialysis
separation
permselectivity
