Zhao Yini, Sun Jianmin, Cao Shuang, Yu Tao, Niu Na, Chen Ligang
College of Chemistry, Chemical Engineering and Resource Utilization, Key Laboratory of Forest Plant Ecology, Northeast Forestry University, 26 Hexing Road, Harbin, 150040, China.
Environ Monit Assess. 2025 Jul 16;197(8):921. doi: 10.1007/s10661-025-14408-5.
Designing simple and efficient biochar adsorbents for removing chemical oxygen demand (COD) is of great significance for environmental protection and human health. In this study, phenol was used as a model pollutant. KCO-modified soybean straw biochar (CSBC) with efficient adsorption properties was simply synthesized for the removal of COD from wastewater. KCO generated CO gas with carbon and formed bubbles in the biochar. When the bubbles ruptured, a substantial number of pores emerged on the cover of biochar, providing a mass of adsorption sites. Furthermore, the modification of KCO caused more oxygen-containing functional groups to appear in the biochar, which greatly improved the adsorption performance. The physicochemical structure of CSBC was studied by a battery of characterization methods. The adsorption experiments showed that CSBC had a good removal effect on COD, and the removal rate could reach 91.07% after 25 min of adsorption. Density functional theory (DFT) analysis revealed that the potential interaction forces between CSBC and phenol were hydrogen bonding, π-π interaction, and electrostatic interaction. In addition, CSBC still has good adsorption effect after 5 times of recycling. It may provide new ideas for the development of economical, high-efficiency and reusable adsorbents to remove COD from wastewater.
设计简单高效的生物炭吸附剂用于去除化学需氧量（COD）对环境保护和人类健康具有重要意义。本研究中，以苯酚作为模型污染物。简单合成了具有高效吸附性能的KCO改性大豆秸秆生物炭（CSBC）用于去除废水中的COD。KCO与碳生成CO气体并在生物炭中形成气泡。当气泡破裂时，生物炭表面出现大量孔隙，提供了大量吸附位点。此外，KCO的改性使生物炭中出现更多含氧官能团，极大地提高了吸附性能。通过一系列表征方法研究了CSBC的物理化学结构。吸附实验表明，CSBC对COD具有良好的去除效果，吸附25分钟后去除率可达91.07%。密度泛函理论（DFT）分析表明，CSBC与苯酚之间的潜在相互作用力为氢键、π-π相互作用和静电相互作用。此外，CSBC经过5次循环使用后仍具有良好的吸附效果。它可能为开发经济、高效且可重复使用的吸附剂以去除废水中的COD提供新思路。
