Loading…

Antimony oxidation and adsorption by in-situ formed biogenic Mn oxide and Fe–Mn oxides

Antimony(Sb), which can be toxic at relatively low concentrations, may co-exist with Mn(Ⅱ)and/or Fe(Ⅱ) in some groundwater and surface water bodies. Here we investigated the potential oxidation and adsorption pathways of Sb(Ⅲ and V) species in the presence of Mn(Ⅱ) and Mn-oxidizing bacteria, with or...

Full description

Saved in:
Bibliographic Details
Published in:Journal of environmental sciences (China) 2017-04, Vol.54 (4), p.126-134
Main Authors: Bai, Yaohui, Jefferson, William A., Liang, Jinsong, Yang, Tingting, Qu, Jiuhui
Format: Article
Language:English
Subjects:
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Antimony(Sb), which can be toxic at relatively low concentrations, may co-exist with Mn(Ⅱ)and/or Fe(Ⅱ) in some groundwater and surface water bodies. Here we investigated the potential oxidation and adsorption pathways of Sb(Ⅲ and V) species in the presence of Mn(Ⅱ) and Mn-oxidizing bacteria, with or without Fe(Ⅱ). Batch experiments were conducted to determine the oxidation and adsorption characteristics of Sb species in the presence of biogenic Mn oxides(BMOs), which were formed in-situ via the oxidation of Mn(Ⅱ) by a Mn-oxidizing bacterium(Pseudomonas sp. QJX-1). Results indicated that Sb(Ⅲ) ions could be oxidized to Sb(V) ions by BMO, but only Sb(V) originating from Sb(Ⅲ) oxidation was adsorbed effectively by BMO. Introduced Fe(Ⅱ) was chemically oxidized to Fe OOH, the precipitates of which mixed with BMO to form a new compound, biogenic Fe–Mn oxides(BFMO). The BMO part of the BFMO mainly oxidized and the Fe OOH of the BFMO mainly adsorbed the Sb species. In aquatic solutions containing both As(Ⅲ) and Sb(Ⅲ), the BFMO that formed in-situ preferentially oxidized Sb over As but adsorbed As more efficiently. Chemical analysis and reverse transcription real-time polymerase chain reaction revealed that the presence of Fe(Ⅱ), As(Ⅲ) and Sb(Ⅲ) accelerated the oxidation of Mn(Ⅱ) but inhibited the activity of Mn-oxidizing bacteria. These results provide significant insights into the biogeochemical pathways of Sb, Mn(Ⅱ) in aquatic ecosystems, with or without Fe(Ⅱ).
ISSN:1001-0742
1878-7320
DOI:10.1016/j.jes.2016.05.026