Control the greenhouse gas emission via mediating the dissimilatory iron reduction: Fulvic acid inhibit secondary mineralization of ferrihydrite

被引：28

作者：

Wang, Mingwei ^{[1
,3
]}

Zhao, Zhiqiang ^{[1
]}

Li, Yang ^{[2
]}

Liang, Song ^{[1
]}

Meng, Yutong ^{[1
]}

Ren, Tengfei ^{[3
]}

Zhang, Xiaoyuan ^{[3
]}

Zhang, Yaobin ^{[1
]}

机构：

[1] Dalian Univ Technol, Sch Environm Sci & Technol, 2 Linggong Rd, Dalian 116024, Liaoning, Peoples R China

[2] Dalian Univ Technol, Sch Ocean Sci & Technol, 2 Dagong Rd, Panjin 124221, Liaoning, Peoples R China

[3] Tsinghua Univ, Sch Environm, State Key Joint Lab Environm Simulat & Pollut Cont, Beijing 100084, Peoples R China

来源：

WATER RESEARCH | 2022年 / 218卷

关键词：

Iron reduction; Ferrihydrite; Humic substances; Greenhouse gas emission; X-ray absorption spectra; Quantum chemical calculation; SEQUENTIAL EXTRACTION PROCEDURE; ENHANCING ANAEROBIC-DIGESTION; ORGANIC-MATTER; METHANE PRODUCTION; ELECTRON-TRANSFER; ENERGY-METABOLISM; HUMIC-ACID; CARBON; TRANSFORMATION; WASTE;

D O I：

10.1016/j.watres.2022.118501

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Reducing methane emission is of great importance to control the global greenhouse effect. Dissimilatory iron reduction (DIR) coupling of organic matter decomposition may suppress methane production via reducing primary electron donors available for methanogenesis. However, during DIR, the amorphous iron oxides (e.g., ferrihydrite) are easy to transform into more stable crystalline iron minerals, which slowdowns the rate of DIR. Humic substance (HS) with redox activity has been extensively reported to facilitate DIR via "electron shuttles" mechanism, yet little known about the effect of HS on mediating the mineralization of iron oxides and the subsequent influences on DIR and methanogenesis. To clarify this, ferrihydrite and fulvic acid (FA) (as the model substance of HS) were supplied to anaerobic methanogenesis systems. Results showed that FA could significantly decrease the formation of crystalline iron oxides, enhance DIR rate by 13.72% and suppress methanogenesis by 25.13% compared to ferrihydrite supplemented only. By X-ray absorption spectra analysis, it was found that FA could complex with ferrihydrite via forming a Fe-C/O structure on the second shell of Fe atom. Quantum chemical calculation further confirmed that FA reduced the adsorption energy between Fe(II) and ferrihydrite. Our study suggested that rational use of HS to mediate mineralization pathway of iron oxides could efficiently improve the availability of iron oxides to drive DIR and control the conversion of organics into CH4 in natural or engineered systems.

引用

页数：13