Analysis of monomeric and competitive adsorption mechanisms of nutrient ions on biochar surfaces based on molecular dynamics simulations

作者：Jikai Lu, Yan Li, Bing Wang, Tong Zhao, Meng Wang, Hongyu Si · 发表于：Bioresource Technology · 年份：2024 · DOI：10.1016/j.biortech.2024.131746 · 被引用次数：27 · 研究领域：Adsorption and biosorption for pollutant removal、Phosphorus and nutrient management、Soil and Water Nutrient Dynamics

This study explores the mechanisms of monomeric and competitive nutrient ion adsorption on biochar surfaces using molecular dynamics simulations and experimental data. C 6 H 12 O 6 offers low-energy adsorption sites for ammoniacal nitrogen, while C-SH and C-NH 2 facilitate adsorption for nitrate nitrogen and available phosphorus. Available potassium is primarily adsorbed near the benzene ring. Structures like C 5 H 10 O 5 and C 4 H 7 NO 4 contribute through physical and chemical adsorption mechanisms. The presence of mesopores enhances adsorption stability. In competitive systems, ammoniacal nitrogen adsorption remains largely unaffected by nitrate nitrogen and available phosphorus, although available potassium negatively impacts it. Nitrate nitrogen is influenced by electrostatic and intermolecular forces, and available phosphorus inhibits its adsorption, while available potassium aids nitrate nitrogen adsorption through ion reactions. This study elucidates the competitive adsorption mechanisms of biochar, providing theoretical support for industrial-scale preparation of nutrient-rich biochar.