Transformation of landfill leachate into in-situ iron-carbon galvanic stabilizer for effective remediation of mercury-contaminated soils: a sustainable solution.

In the intricate soil microenvironment, mercury (Hg) species significantly impact microbial community composition, modulating growth rates and metabolic capabilities, ultimately declining activity levels, impairing ecosystem stability and function, and weakening soil ecological functions, resilience, health, and sustainability. This study explores a sustainable solution for Hg-contaminated soil remediation by transforming landfill leachate into an in-situ iron-carbon galvanic stabilizer (IS-Fe-C-NTP) via combined pyrolysis and nonthermal plasma (NTP) activation. The IS-Fe-C-NTP was utilized to stabilize Hg contaminants in spiked soil samples. Our key findings indicate that the leaching concentrations of stabilized soil samples ranged from 4.62 to 16.39 mg/L, with the stabilization period emerging as the most critical factor influencing the entire stabilization process, significantly modulating the effectiveness of other factors. The leaching dynamics of stabilized Hg were appropriately fitted by Fick's diffusion model, progressing through two phases under varying acidic pH conditions. This study provides a potent, eco-friendly customized solution for remediating mercury-contaminated soils, emphasizing the importance of understanding the chemical nature of the stabilizer and its interactions with soil constituents.