The effects of Fe2+ on sulfur-oxidizing bacteria (SOB) driven autotrophic denitriﬁcation

Shulong Wen; Keqiang Hu; Yuancai Chen; Yongyou Hu

doi:10.1016/j.jhazmat.2019.03.059

The effects of Fe²⁺ on sulfur-oxidizing bacteria (SOB) driven autotrophic denitriﬁcation

J Hazard Mater. 2019 Jul 5:373:359-366. doi: 10.1016/j.jhazmat.2019.03.059. Epub 2019 Mar 16.

Authors

Shulong Wen¹, Keqiang Hu², Yuancai Chen³, Yongyou Hu²

Affiliations

¹ Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, State Key Laboratory of Pulp and Paper Engineering, College of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China. Electronic address: 80317597@qq.com.
² Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, State Key Laboratory of Pulp and Paper Engineering, College of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China.
³ Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, State Key Laboratory of Pulp and Paper Engineering, College of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China. Electronic address: chenyc@scut.edu.cn.

PMID: 30933858
DOI: 10.1016/j.jhazmat.2019.03.059

Abstract

With the short-term exposure to Fe²⁺, the mechanism of autotrophic denitrification and sulfide oxidation and the correlation between microbial community changes and environmental factors have been explored in the ADSOB process. RSM was used to optimize conditions for the maximum nitrate reduction and sulfide oxidation. About 88% of nitrate could be autotrophically denitrified to nitrogen by utilizing sulfide as the electron donor with the molar ratio C/N of 1.14 and S/N of 0.99 at pH 7.1. Lower Fe²⁺ additions can reduce TDS inhibition with dissolved sulfide to form FeS precipitates, while high amount of Fe²⁺ limited the mass transfer of NO₃^- and intermediate products such as S⁰ may be generated. High-throughput sequencing and RDA analysis revealed the correlation between ferrous iron, environmental factors and microorganisms. Sulfurospirillum, Rhodanobacter, Thauera and Thiobacillus were all slightly promoted at NFL level and inhibited at NFH level. And the narrow angles of the arrows indicated that Thauera, Sulfurospirillum and Thiobacillus were positively correlated with SO₄^2- concentrations, while large angles indicated these bacteria were inversely related with TDS and NO₃- arrows, which further confirmed that these bacteria played a dominant role in the ADSOB process, and can reduce NO₃- by the oxidation of TDS. The correlation further indicated that lower Fe²⁺ additions have a promoting effect, while high concentrations have an inhibiting effect.

Keywords: Autotrophic denitriﬁcation; Microorganisms; Sulfide oxidation; TDS.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Autotrophic Processes
Denitrification*
Iron / administration & dosage*
Nitrates / metabolism
Oxidation-Reduction
Sulfur / metabolism*
Thauera / drug effects*
Thiobacillus / drug effects*

Substances

Nitrates
Sulfur
Iron