Publication
Title
Effect of humic acids on heavy metal removal by zero-valent iron in batch and continuous flow column systems
Author
Abstract
The effects of Aldrich humic acids (HA) on the removal of Zero-valent iron (ZVI) was investigated in laboratory systems. In batch, the removal rate of Zn and Ni (5 mg 1(-1)) was, respectively, 2.8 and 2.4 times lower in the presence of HA (20 mg 1(-1)) than in the absence of HA, presumably due to the formation of HA-heavy metal complexes which prevented the removal reactions at the ZVI surface. Chromate removal was not affected. In a column test, two parallel systems were supplemented with a continuous input of simulated groundwater containing a mixture of the heavy metals Zn, Ni and Cr(VI) (5 mg 1(-1) each), with or without HA (at 20 mg 1(-1)). Initially, the two column systems efficiently (> 90%) removed the heavy metals from the simulated groundwater. When the input heavy metal concentration was increased to 8-10 mg 1(-1), a significant breakthrough of Ni and Zn, up to 80%, occurred in the column system fed with HA. Chromate and HA did not significantly break through. After 60 weeks, the effect of HA on leaching of the accumulated metals (approx. 2 mg g(-1)) was investigated. No significant leaching was observed. The results of this study suggest that the impact of dissolved organic matter on the efficiency and lifetime of a ZVI barrier for in situ removal of heavy metals should be considered in the design of the barrier.
Language
English
Source (journal)
Water research / International Association on Water Pollution Research. - Oxford, 1967, currens
Publication
Oxford : 2005
ISSN
0043-1354
Volume/pages
39(2005), p. 3531-3540
ISI
000232417800011
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 27.09.2013
Last edited 05.08.2017
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