School of Resources and Environment, Northeast Agricultural University, Harbin 150030, China.
School of Resources and Environment, Northeast Agricultural University, Harbin 150030, China; Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, 4888 Shengbei Rd, Changchun 130102, China.
J Hazard Mater. 2022 Mar 5;425:127876. doi: 10.1016/j.jhazmat.2021.127876. Epub 2021 Nov 25.
Sulfur-iron functionalized biochar (BC-Fe-S) was designed by simultaneously supporting FeO nanoparticles and grafting sulfur-containing functional groups onto biochar to stabilize Pb and Cd in soil. The BC-Fe-S exhibited excellent stabilization performance for Pb and Cd with fast kinetic equilibrium within 5 days associating with pseudo-second-order model. The bioavailable-Pb and -Cd contents decreased by 59.22% and 70.28% with 3% BC-Fe-S treatment after 20 days of remediation. Speciation transformation analysis revealed that the increase of stabilization time and BC-Fe-S dosage with appropriate soil moisture and pH promoted toxicities decrease of Pb and Cd with transformation of labile fractions to more steady fractions. The labile fractions of Pb and Cd decreased by 12.22% and 16.21% with 3% BC-Fe-S treatment, and transformed to the residual speciation. Meanwhile, wetting-drying and freezing-thawing aging did not markedly alter the bioavailability of Pb and Cd, proving that the BC-Fe-S holds promise for stabilization of Pb and Cd in varying environmental conditions. 16S rRNA sequencing analysis demonstrated that the BC-Fe-S significantly improved diversity and composition of microbial community, especially increasing the relative abundance of heavy metal-resistant bacteria. Overall, these results suggested BC-Fe-S as a high-performance and environmental-friendly amendment with stability to remediate heavy metals polluted soil.
硫铁功能化生物炭 (BC-Fe-S) 通过同时负载 FeO 纳米颗粒和接枝含硫官能团到生物炭上来设计，以稳定土壤中的 Pb 和 Cd。BC-Fe-S 对 Pb 和 Cd 表现出优异的稳定性能，在 5 天内达到快速动力学平衡，符合准二级模型。经过 20 天的修复，用 3%BC-Fe-S 处理后，生物可利用态-Pb 和 -Cd 含量分别降低了 59.22%和 70.28%。形态转化分析表明，随着稳定时间的延长和 BC-Fe-S 用量的增加，适当的土壤水分和 pH 值促进了 Pb 和 Cd 毒性的降低，使不稳定分数向更稳定分数转化。用 3%BC-Fe-S 处理后，Pb 和 Cd 的不稳定分数分别降低了 12.22%和 16.21%，转化为残余形态。同时，干湿和冻融老化并没有显著改变 Pb 和 Cd 的生物可利用性，证明 BC-Fe-S 有望在不同的环境条件下稳定 Pb 和 Cd。16S rRNA 测序分析表明，BC-Fe-S 显著提高了微生物群落的多样性和组成，特别是增加了重金属抗性细菌的相对丰度。总的来说，这些结果表明 BC-Fe-S 是一种高性能和环境友好的修复剂，对稳定修复重金属污染土壤具有稳定性。
