School of Water Resources & Environmental Engineering, East China University of, Technology, Nanchang 330013, China.
School of Water Resources & Environmental Engineering, East China University of, Technology, Nanchang 330013, China; Jiangxi Provincial Key Laboratory of Genesis and Remediation of Groundwater Pollution, Nanchang 330013, China.
Ecotoxicol Environ Saf. 2024 Aug;281:116601. doi: 10.1016/j.ecoenv.2024.116601. Epub 2024 Jun 18.
In this study, a novel sulfur/zinc co-doped biochar (SZ-BC) stabilizer was successfully developed for the remediation of mercury-contaminated soil. Results from SEM, TEM, FTIR and XRD revealed that biochar (BC) was successfully modified by sulfur and zinc. In the batch adsorption experiments, the sulfur-zinc co-pyrolysis biochar displayed excellent Hg(II) adsorption performance, with the maximum adsorption capacity of SZ-BC (261.074 mg/g) being approximately 16.5 times that of BC (15.855 mg/g). Laboratory-scale static incubation, column leaching, and plant pot experiments were conducted using biochar-based materials. At an additional dosage of 5 % mass ratio, the SZ-BC exhibits the most effective stabilization of mercury in soil, leading to a significant reduction in leaching loss compared to the control group (CK) by 51.30 %. Following 4 weeks of incubation and 2 weeks of leaching with SZ-BC, the residual mercury in the soil increased by 27.84 %. As a result, potential ecological risk index of mercury decreased by 92 % compared to the CK group. In the pot experiment, SZ-BC significantly enhanced the growth of Chinese cabbage, with biomass and root dry weight reaching 3.20 and 2.80 times that of the CK group, respectively. Additionally, the Translocation Factor (TF) and Bioconcentration Factor (BF) were reduced by 44.86 % and 74.43 %, respectively, in the SZ-BC group compared to the CK group. Moreover, SZ-BC can effectively improve enzyme activities and increase microbial communities in mercury-contaminated soils. The mechanisms of adsorption and stabilization were elucidated through electrostatic adsorption, ion exchange, surface complexation, and precipitation. These findings provide a potentially effective material for stabilizing soils contaminated with mercury.
在这项研究中，成功开发了一种新型的硫/锌共掺杂生物炭（SZ-BC）稳定剂，用于修复受汞污染的土壤。SEM、TEM、FTIR 和 XRD 的结果表明，生物炭（BC）成功地被硫和锌修饰。在批量吸附实验中，硫-锌共热解生物炭显示出优异的 Hg(II)吸附性能，SZ-BC 的最大吸附容量（261.074 mg/g）约为 BC（15.855 mg/g）的 16.5 倍。使用基于生物炭的材料进行了实验室规模的静态孵育、柱浸出和盆栽实验。在额外添加 5%质量比的用量下，SZ-BC 对土壤中汞的稳定效果最为显著，与对照组（CK）相比，浸出损失减少了 51.30%。经过 4 周的孵育和 2 周的 SZ-BC 浸出后，土壤中残留的汞增加了 27.84%。因此，与 CK 组相比，汞的潜在生态风险指数降低了 92%。在盆栽实验中，SZ-BC 显著促进了白菜的生长，其生物量和根干重分别达到 CK 组的 3.20 倍和 2.80 倍。此外，SZ-BC 组的迁移因子（TF）和生物浓缩因子（BF）分别比 CK 组降低了 44.86%和 74.43%。此外，SZ-BC 可以有效地提高受汞污染土壤中的酶活性并增加微生物群落。通过静电吸附、离子交换、表面络合和沉淀等机制阐明了吸附和稳定的机制。这些发现为稳定受汞污染的土壤提供了一种潜在有效的材料。
