The Role of Amorphous C-O-Fe Structures in Degrading Tetracycline Using Biochar-Based Catalysts

Red mud-modified lotus leaf biochar activates peroxydisulfate (PDS) for efficient tetracycline degradation. The C-O-Fe structure in the biochar enhances electron transfer and iron cycling, generating reactive oxygen species for pollutant removal and reducing toxicity in wastewater.

October 4, 2024

1–2 minutes

Song, et al (2024) Unraveling the mechanism and the key role of amorphous structure C-O-Fe in tetracycline degradation by activation of persulfate in lotus leaf-based red mud-modified biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More. *Chemical Engineering Journal.* https://doi.org/10.1016/j.cej.2024.156078

A recent study published in the Chemical Engineering Journal explores the effectiveness of red mud-modified biochar in degrading tetracycline (TC), a common antibiotic contaminant in water systems. The researchers used lotus leaf biochar modified with red mud (RM-HBC) to activate peroxydisulfate (PDS), a strong oxidant, achieving a high TC removal rate of 98.61%.

The key to this process is the formation of an amorphous C-O-Fe structure within the biochar. This structure facilitates electron transfer, enhancing the cyclic transformation of iron (Fe) between its Fe(II) and Fe(III) states. This cycle is crucial for generating reactive oxygen species (ROS) like singlet oxygen (¹O₂) and hydroxyl radicals (·OH), which are responsible for breaking down TC.

The study demonstrated that the RM-HBC system not only optimizes the degradation of TC but also reduces its toxicity. The C-O-Fe structure enriched the biochar’s electron density, improving PDS activation efficiency and leading to the formation of Fe₃O₄ crystals as a byproduct. By using low-cost materials like lotus leaves and red mud, the research offers a sustainable solution for wastewater treatment while reusing industrial waste.

This work provides insights into the potential of red mud as an alternative to expensive metal salts in biochar modification, enhancing large-scale environmental applications.