Water treatment using silver-iron-modified biochar for enhanced disinfection and sustainability

Abstract

The contamination of water resources by pathogenic microorganisms remains a critical global challenge, predominantly in low- and middle-income countries. Conventional water treatment technologies, such as chlorination and filtration, often face drawbacks, including the formation of harmful byproducts and high operational costs. The increasing demand for efficient, sustainable, and scalable solutions necessitates the exploration of advanced materials for water disinfection. This study investigates the potential of silver-iron (Ag-Fe)-modified biochar as a photocatalyst under visible light to achieve high microbial inactivation. The material demonstrates dual functionality through the antibacterial effects of Ag and the photocatalytic activity of Fe, integrated within a renewable biochar. Elemental composition analysis shows that a composition of 4.3 wt% Ag and 30.0 wt% Fe enhances antimicrobial performance. Experimental results indicate bacterial inactivation under visible light conditions. Ag-Fe-modified biochar presents a potential alternative to conventional disinfection methods.

Keywords

Photocatalysis / Biochar / Water disinfection / Silver / Iron catalysis

Funding

The authors Tiong Tung Chuan and Peter Nai Yuh Yek would like to thank the University of Technology Sarawak for providing financial support under the UTS Internal Research Grant(UCTS/RESEARCH/<3/2023/02) to perform this project

Conflict of interest

Su Shiung Lam is an Associate Editor of this journal, but was not in any way involved in the editorial and peer-review process conducted for this paper, directly or indirectly. The authors declare they have no competing interests.

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