Effect of N-hydroxyethyl-ethylenediamine-triacetic acid (HEDTA) on Cr(VI) reduction by Fe(II).

Abstract:

:The complexation of Fe(II) with organic ligand results in the decrease of redox potential, and enhances the reduction ability of Fe(II). An important example is the use of Fe(II)-organic complexes to accelerate Cr(VI) reduction. Dissolved O(2) and light can potentially affect Cr(VI) reduction; however, these two factors have not been adequately evaluated. A batch technique was used to investigate the Cr(VI) reduction as influenced by the light and dissolved O(2) using N-hydroxyethyl-ethylenediamine-triacetic acid (HEDTA) and Fe(II) solutions. The oxidation of Fe(II) by dissolved O(2) was rapid in the presence of HEDTA at low pH; nonetheless, the oxidation proceeded slowly when HEDTA was absent. Although Cr(VI) could be reduced by free Fe(II) at low pH, the reaction was considerably slower than that of systems involving HEDTA. The enhancement of Cr(VI) reduction by Fe(II) in the presence of high concentrations of HEDTA was achieved as a result of two processes. First, HEDTA acted as a ligand for expediting electron transfer between Fe(II) and Cr(VI). Secondly, HEDTA served as a reductant for Cr(VI) under illumination.

journal_name

Chemosphere

journal_title

Chemosphere

authors

Tzou YM,Wang MK,Loeppert RH

doi

10.1016/S0045-6535(03)00002-X

subject

Has Abstract

pub_date

2003-06-01 00:00:00

pages

993-1000

issue

9

eissn

0045-6535

issn

1879-1298

pii

S0045-6535(03)00002-X

journal_volume

51

pub_type

杂志文章