Li Yingquan, Zhao Baowei, Shang Tingting
School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, Gansu, People's Republic of China.
Gansu Dust Suppression for Transportation and Storage Engineering Research Center, Lanzhou, 730070, Gansu, People's Republic of China.
Sci Rep. 2025 Jul 10;15(1):24948. doi: 10.1038/s41598-025-09880-5.
Both biochar and humic acid adsorb heavy metals, but their combined effect has rarely been reported. In this paper, the adsorption of Cu(II) by single biochar (BS) and biochar with humic acid (BS + HA) in aqueous solution were studied, and the effects of solution pH, initial Cu(II) concentration, temperature and Ca ionic strength on the adsorption of Cu(II) were investigated. The results showed that under the same time, the adsorption of Cu(II) under the BS and BS + HA systems showed an increasing trend with the increase of pH, and the maximum adsorption capacity of the BS + HA system was reached at a pH of about 4, while the BS system alone exhibited a noticeable lag. The increase of the initial concentration of Cu(II) also promoted the adsorption capacity of the two systems, and the adsorption of Cu(II) by the BS and the BS + HA systems was a spontaneous adsorption process, and the elevation of the temperature effectively promoted the adsorption of Cu(II). The addition of Ca could promote the adsorption efficacy of the single BS system, but had little effect on the BS + HA system. Overall, the BS + HA system showed better adsorption than the single BS system, and the addition of humic acid enhanced the adsorption performance of biochar to Cu(II). The results could provide a theoretical basis for the combined action of biochar and humic acid on the remediation of Cu(II) contaminated water.
生物炭和腐殖酸都能吸附重金属，但它们的联合作用鲜有报道。本文研究了单一生物炭（BS）和生物炭与腐殖酸（BS + HA）在水溶液中对Cu(II)的吸附情况，并考察了溶液pH值、初始Cu(II)浓度、温度和Ca离子强度对Cu(II)吸附的影响。结果表明，在相同时间内，BS和BS + HA体系下Cu(II)的吸附量随pH值升高呈增加趋势，BS + HA体系在pH约为4时达到最大吸附量，而单独的BS体系则出现明显滞后。Cu(II)初始浓度的增加也促进了两个体系的吸附能力，BS和BS + HA体系对Cu(II)的吸附是一个自发吸附过程，温度升高有效促进了Cu(II)的吸附。Ca的加入可促进单一BS体系的吸附效果，但对BS + HA体系影响不大。总体而言，BS + HA体系比单一BS体系表现出更好的吸附性能，腐殖酸的加入增强了生物炭对Cu(II)的吸附性能。研究结果可为生物炭和腐殖酸联合作用修复Cu(II)污染水体提供理论依据。
