Remediation of cadmium and lead polluted soil using thiol-modified biochar
Remediation of cadmium and lead polluted soil using thiol-modified biochar
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DOI：
10.1016/j.jhazmat.2020.122037
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发表时间：
2020-04-15
影响因子：
13.6
通讯作者：
Hou, Yanwei
中科院分区：
文献类型：
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作者：
Fan, Jiajun;Cai, Chao;Hou, Yanwei
通过与β-巯基乙醇的酯化反应制备了硫醇修饰的稻草生物炭，并将其用于修复Cd、Pb污染的土壤。通过元素分析、BET分析、FE-SEM、FT-IR和XPS对改性生物炭进行了表征。这些分析结果表明，硫醇基团成功地接枝到了生物炭的表面，并参与了金属离子的络合。间歇吸附实验表明，RS对Cd~(2+)、Pb~(2+)的吸附符合准二级动力学模型和Langmuir等温式。单一金属体系对Cd~(2+)和Pb~(2+)的最大吸附容量分别为45.1和61.4 mg·g~(-1)。在二元金属体系中，RS在Pb2+上选择性吸附Cd~(2+)。Cd~(2+)和Pb~(2+)主要通过表面络合去除。在土壤培养试验中(28d)，RS使土壤有效Cd减少了34.8-39.2%，而RS减少了8.6%-11.1%。这项研究表明RS是修复重金属污染土壤的一种潜在有效的改良剂。
Thiol-modified rice straw biochar (RS) was prepared by an esterification reaction with beta-mercaptoethanol and used for the remediation of Cd and Pb polluted soils. Modified biochar was characterized through elemental analysis, BET analysis, FE-SEM, FT-IR and XPS. These analytical results revealed that thiol groups were successfully grafted onto the surface of the biochar and were involved in metal ion complexation. Batch sorption experiments indicated that Cd2+ and Pb2+ sorption onto RS described well by a pseudo second order kinetic model and a Langmuir isotherm. The maximum adsorption capacities for Cd2+ and Pb2+, in the single-metal systems, were 45.1 and 61.4 mg g(-1), respectively. In the binary-metal systems, RS selectively adsorbed Cd2+ over Pb2+ . Cd2+ and Pb2+ were removed mainly through surface complexation. In the soil incubation experiments (28 days), RS reduced the available Cd by 34.8-39.2 %; while, RS reduced the available Pb by 8.6 %-11.1 %. This research demonstrates RS as a potentially effective amendment for the remediation of heavy metal polluted soils.