Arsenite and ferrous iron oxidation linked to chemolithotrophic denitrification for the immobilization of arsenic in anoxic environments.

ABSTRACT: The objective of this study was to explore a bioremediation strategy based on injecting NO3- to support the anoxic oxidation of ferrous iron (Fe(II)) and arsenite (As(II)) in the subsurface as a means to immobilize As in the form of arsenate (As(V)) adsorbed onto biogenic ferric (Fe(III)) (hydr)oxides. Continuous flow sand filled columns were used to simulate a natural anaerobic groundwater and sediment system with co-occurring As(III) and Fe(II) in the presence (column SF1) or absence (column SF2) of nitrate, respectively. During operation for 250 days, the average influent arsenic concentration of 567 microg L(-1) was reduced to 10.6 (+/-9.6) microg L(-1) in the effluent of column SF1. The cumulative removal of Fe(II) and As(II) in SF1 was 6.5 to 10-fold higher than that in SF2 Extractio

SUBMITTER: Sun W 

PROVIDER: S-EPMC4532354 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature