Work

Anaerobic formation of manganese oxides mediated by complexed iron and application in tetracycline hydrochloride degradation

Year: 2026

Type: article

Abstract: Biological manganese oxides (BioMnOx) are promising materials for micro-pollutant degradation, with conventional synthesis primarily mediated by aerobic microorganisms and dependent on high-potential oxidants (e.g., O 2 , NO 3 − ). In this study, light-driven anaerobic synthesis of BioMnOx was investigated using the photosynthetic bacterium Rubrivivax benzoatilyticus , and its application in tetracycline hydrochloride (TC) degradation under anaerobic conditions was evaluated. Results showed that in the presence of potassium ferrocyanide, R. benzoatilyticus could extracellularly oxidize Mn 2+ to BioMnOx anaerobically. The ferrocyanide potassium firstly was biologically oxidized to ferricyanide potassium under photo-anaerobic conditions, and then Mn 2+ was abiotically oxidized to BioMnOx by ferricyanide potassium. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) confirmed that aqueous Mn 2+ was converted to mixed-valence Mn 3 O 4 , with concurrent co-precipitation of Mn 3 (PO 4 ) 2 . TC degradation experiments demonstrated that approximately 40.24% TC removal was achieved with 20 mg/L BioMnOx under near-neutral conditions, while acidic environments significantly enhanced its oxidation performance. The maximum TC removal efficiency of 89.10% was attained at 40 mg/L BioMnOx and pH 3. UV–Vis spectroscopy and liquid chromatography-mass spectrometry (LC-MS) detected multiple degradation intermediates of TC, confirming that TC was oxidized by BioMnOx rather than simply adsorbed. This work provides an effective strategy for the anaerobic synthesis of BioMnOx and the degradation of TC, offering new insights into the micro-pollutants removal via manganese cycling in anaerobic aquatic environments.

Source: Journal of Water Process Engineering

DOI: 10.1016/j.jwpe.2026.109658

Authors: Liu Yang, Yiming Wang, Lixin Huo, Xingzu Wang

Institutions: Chinese Academy of Sciences, Chongqing Institute of Green and Intelligent Technology, University of Chinese Academy of Sciences

Language: English

Topic: Advanced oxidation water treatment

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Clean water and sanitation, Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $3,350