Concentration and purification of chromate from electroplating wastewater by two-stage electrodialysis processes

doi:10.1016/j.jhazmat.2008.04.106

機構典藏 > College of Engineering > Graduate Institute & Department of Water Resources and Environmental Engineering > Journal Article > Item 987654321/44714

Please use this identifier to cite or link to this item: https://tkuir.lib.tku.edu.tw/dspace/handle/987654321/44714

Title:	Concentration and purification of chromate from electroplating wastewater by two-stage electrodialysis processes
Authors:	Chen, Shiao-shing;Li, Chi-wang;Hsu, Hong-der;Lee, Po-ching;Chang, Yu-min;Yang, Chia-hao
Contributors:	淡江大學水資源與環境工程學系
Keywords:	Chromate;Concentration;Purification;Two-stage electrodialysis;Electroplating wastewater
Date:	2009-01
Issue Date:	2010-08-10 11:24:34 (UTC+8)
Publisher:	Elsevier BV
Abstract:	A designed two-stage electrodialysis system is proposed to concentrate and purify chromate from a low pH electroplating wastewater using monovalent selective electrodialysis membranes. With low pH of the raw water (pH 2.2) in the first stage, chromate was presented as HCrO4− and monovalent ions (HCrO4−, NH2SO3−, Na+ and Cl−) were able to pass through the membrane thus chromate was concentrated up to 191%. Higher current density, flowrate and more membrane area all increased the chromium recovery. When pH was adjusted to 8.5 before entering the second stage, the chromate species was presented as divalent CrO42− and retained in the concentrated stream, and the rest monovalent ions (NH2SO3−, Na+ and Cl−) were separated by passing through the membrane. For example, 45% of the chlorides were separated in this study. The separation efficiencies in the second stage were also increased when the current density, flowrate and membrane area were increased. Electron Spectroscopy for Chemical Analysis was used to examine the surface chromate species for stage 1, and anion exchange membrane showed more chromate fouling comparing to cation exchange membrane due to more adsorption and concentration polarization effects for the anion exchange membrane.
Relation:	Journal of Hazardous Materials 161(2-3), pp.1075-1080
DOI:	10.1016/j.jhazmat.2008.04.106
Appears in Collections:	[Graduate Institute & Department of Water Resources and Environmental Engineering] Journal Article

Files in This Item:

File	Description	Size	Format
0304-3894_161(2-3)p1075-1080.pdf		546Kb	Adobe PDF	509	View/Open
1-s2.0-S0304389408006043-main.pdf		546Kb	Adobe PDF	3	View/Open

Loading...