Roles of zero-valent iron in anaerobic digestion: Mechanisms, advances and perspectives

Zhang-Wei He; Zheng-Shuo Zou; Yong-Xiang Ren; Cong-Cong Tang; Ai-Juan Zhou; Wenzong Liu; Ling Wang; Zhihua Li; Aijie Wang

doi:10.1016/j.scitotenv.2022.158420

Roles of zero-valent iron in anaerobic digestion: Mechanisms, advances and perspectives

Sci Total Environ. 2022 Dec 15:852:158420. doi: 10.1016/j.scitotenv.2022.158420. Epub 2022 Aug 30.

Authors

Zhang-Wei He¹, Zheng-Shuo Zou², Yong-Xiang Ren², Cong-Cong Tang², Ai-Juan Zhou³, Wenzong Liu⁴, Ling Wang⁵, Zhihua Li², Aijie Wang⁴

Affiliations

¹ Shaanxi Key Laboratory of Environmental Engineering, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055, China. Electronic address: zwhe@xauat.edu.cn.
² Shaanxi Key Laboratory of Environmental Engineering, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055, China.
³ College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
⁴ State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
⁵ School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266000, China.

PMID: 36049687
DOI: 10.1016/j.scitotenv.2022.158420

Abstract

With the rapid growth of population and urbanization, more and more bio-wastes have been produced. Considering organics contained in bio-wastes, to recover resource from bio-wastes is of great significance, which can not only achieve the resource recycle, but also protect the environment. Anaerobic digestion (AD) has been proved as one of the most promising strategies to recover bio-energy from bio-wastes, as well as to realize the reduction of bio-wastes. However, the conventional interspecies electron transfer is sensitive to environmental shocks, such as high ammonia, organic pollutants, metal ions, etc., which lead to instability or failure of AD. The recent findings have proved that the introduction of zero-valent iron (ZVI) in AD system can significantly enhance methane production from bio-wastes. This review systematically highlighted the recent advances on the roles of ZVI in AD, including underlying mechanisms of ZVI on AD, performance enhancement of AD contributed by ZVI, and impact factors of AD regulated by ZVI. Furthermore, current limitations and outlooks have been analyzed and concluded. The roles of ZVI on underlying mechanisms in AD include regulating reaction conditions, electron transfer mode and function of microbial communities. The addition of ZVI in AD can not only enhance bio-energy recovery and toxic contaminants removal from bio-wastes, but also have the potential to buffer adverse effect caused by inhibitors. Moreover, the electron transfer modes induced by ZVI include both interspecies hydrogen transfer and direct interspecies electron transfer pathways. How to comprehensively evaluate the effects of ZVI on AD and further improve the roles of ZVI in AD is urgently needed for practical application of ZVI in AD. This review aims to provide some references for the introduction of ZVI in AD for enhancing bio-energy recovery from bio-wastes.

Keywords: Anaerobic digestion; Electron transfer mode; Methane production enhancement; Practical application; Zero-valent iron.

Publication types

Review

MeSH terms

Ammonia
Anaerobiosis
Environmental Pollutants*
Hydrogen
Iron*
Methane

Substances

Iron
Ammonia
Methane
Hydrogen
Environmental Pollutants