Treatment of Cyanide-Free Wastewater from Brass Electrodeposition with EDTA by Electrodialysis: Evaluation of Underlimiting and Overlimiting Operations

Author:

Barros Kayo Santana,Scarazzato TatianaORCID,Pérez-Herranz Valentín,Espinosa Denise Crocce RomanoORCID

Abstract

Growing environmental concerns have led to the development of cleaner processes, such as the substitution of cyanide in electroplating industries and changes in the treatment of wastewaters. Hence, we evaluated the treatment of cyanide-free wastewater from the brass electroplating industry with EDTA as a complexing agent by electrodialysis, aimed at recovering water and concentrated solutions for reuse. The electrodialysis tests were performed in underlimiting and overlimiting conditions. The results suggested that intense water dissociation occurred at the cathodic side of the commercial anion-exchange membrane (HDX) during the overlimiting test. Consequently, the pH reduction at this membrane may have led to the reaction of protons with complexes of EDTA-metals and insoluble species. This allowed the migration of free Cu2+ and Zn2+ to the cation-exchange membrane as a result of the intense electric field and electroconvection. These overlimiting phenomena accounted for the improvement of the percent extraction and percent concentration, since in the electrodialysis stack employed herein, the concentrate compartments of cationic and anionic species were connected to the same reservoir. Chronopotentiometric studies showed that electroconvective vortices minimized fouling/scaling at both membranes. The electrodialysis in the overlimiting condition seemed to be more advantageous due to water dissociation and electroconvection.

Publisher

MDPI AG

Subject

Filtration and Separation,Chemical Engineering (miscellaneous),Process Chemistry and Technology

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3