Kwon, Man Jae Yang, Jung-Seok Shim, Moo Joon Boyanov, Maxim I. Kemner, Kenneth M. O'Loughlin, Edward J. 2024-01-20T09:31:43Z 2024-01-20T09:31:43Z 2021-09-05 2014-07 2328-8930 https://pubs.kist.re.kr/handle/201004/126625 Acid extraction followed by a colorimetric assay is a widely use approach for the determination of the total Fe(II) in samples from suboxic and anoxic environments. Under sulfidogenic conditions, these samples can contain both metal sulfides and iron (hydr) oxides. Our comparisons between 0.5 N HCl extraction and X-ray absorption fine structure (XAFS) analysis of systems containing 40 mM Fe(III) as (hydr)oxides and 10 mM FeS showed that the presence of sulfide can result in significant overestimation of the total Fe(II) by acid extraction. The total Fe(II) determined by XAFS was consistent with the added FeS. However, the total Fe(II) determined by extraction was significantly higher dependent on the nature of the Fe(III) (hydr)oxides; the rates and extent of Fe(II) production were higher with ferrihydrite and lepidocrocite than with goethite. Total Fe(II) concentrations determined following acid extraction might be overestimated when iron (hydr)oxides and sulfide minerals are present samples. English AMER CHEMICAL SOC SULFATE-REDUCING BACTERIA CHEMICAL-REDUCTION DISSOLVED SULFIDE MARINE-SEDIMENTS HYDROGEN-SULFIDE FERRIC IRON KINETICS LEPIDOCROCITE DISSOLUTION REACTIVITY Acid Extraction Overestimates the Total Fe(II) in the Presence of Iron (Hydr)oxide and Sulfide Minerals Article 10.1021/ez500152h 1 ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS, v.1, no.7, pp.310 - 314 ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 1 7 310 314 scopus 000350831300004 2-s2.0-84969260509 Engineering, Environmental Environmental Sciences Engineering Environmental Sciences & Ecology Article SULFATE-REDUCING BACTERIA CHEMICAL-REDUCTION DISSOLVED SULFIDE MARINE-SEDIMENTS HYDROGEN-SULFIDE FERRIC IRON KINETICS LEPIDOCROCITE DISSOLUTION REACTIVITY