Work

Remediation of lead-contaminated soil by Fe-Mn-Ni layered double hydroxide composite biochar

Year: 2025

Type: article

Abstract: The accelerated pace of urbanization and industrialization has significantly increased lead (Pb) pollution, emerging as a global environmental concern that threatens ecosystems and human health. This study synthesized a Fe-Mn-Ni LDH-biochar composite (LDH/CSB) using an improved co-precipitation method and evaluated its remediation effect on Pb-contaminated soil. Results demonstrated that LDH/CSB treatment altered the soil's physical and chemical properties, including significant increases in pH, electrical conductivity (EC), and total organic carbon (TOC) content. In soils with varying contamination levels, pH rose by up to 0.35 units post-treatment, while EC increased significantly from 35.26% to 230.23%. TOC also showed considerable enhancement. Furthermore, LDH/CSB effectively reduced the bio-active states of Pb (active Pb and TCLP-Pb). The material's favorable layered structure and high specific surface area (up to 78.70 m²/g), along with numerous functional groups, provide active sites for immobilizing and stabilizing pollutants. This transformation converts easily migratory forms of Pb in soil (Acs-Pb and Red-Pb) into more stable forms (Oxi-Pb and Res-Pb). Pearson correlation analysis indicated a significant positive correlation between soil pH and stable Pb forms (Oxi-Pb and Res-Pb). In conclusion, the remediation mechanism of LDH/CSB is primarily attributed to the morphological transformation of Pb, facilitated by pH elevation and adsorption processes, enhancing the solidification stability of Pb and significantly reducing its bioavailability and ecological risk. Thus, LDH/CSB is a promising strategy for remediating Pb-contaminated soil, providing a viable solution for managing heavy metal pollution.

Source: Chemical Engineering Journal Advances

DOI: 10.1016/j.ceja.2025.100785

Authors: Hongguang Zhou, Yunke Kuang, Yanping Gan, Peng Jiang, Yuying Pu, Yanmei Yang

Institutions: Chongqing Jiaotong University, Chongqing College of Mobile Communication

Language: English

Topic: Heavy metals in environment

Subfield: Pollution

Field: Environmental Science

Domain: Physical Sciences

SDGs: Life on land, Clean water and sanitation, Responsible consumption and production

Open Access status: gold

Estimated APC paid: $2,050