硫化亚铁改性生物炭修复锑污染土壤及修复后稳定性评估  

Remediation of Antimony-polluted Soil Using Iron Sulfide-modified Biochar and Stability Assessment After Remediation

作　　者：张森 李清雨 姜登岭 曹莹[1] 高存富 孟甜 李强[1] ZHANG Sen;LI Qing-yu;JIANG Deng-ling;CAO Ying;GAO Cun-fu;MENG Tian;LI Qiang(Environmental Testing and Experiment Center,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;College of Civil and Architectural Engineering,North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]中国环境科学研究院环境检测与实验中心,北京100012 [2]华北理工大学建筑工程学院,唐山063210

出　　处：《环境科学》2025年第4期2525-2536,共12页Environmental Science

基　　金：国家重点研发计划项目(2020YFC1807703)。

摘　　要：为探究硫化亚铁改性生物炭(FeS-BC)对锑冶炼厂周边污染土壤的修复效果与机制,以贵州省晴隆县某废弃锑冶炼厂周边土壤为研究目标,通过土壤培养试验,对比研究了原始生物炭(BC)和硫化亚铁改性生物炭材料(FeS-BC)对土壤锑(Sb)浸出毒性、有效态含量和赋存形态的影响.结果表明,FeS∶BC质量比为1∶5、投加量为7%时对不同Sb污染程度土壤(G1~G6)中Sb的平均稳定效果最好,达到了66.85%;FeS-BC在较宽的pH范围内(2.0~10.0)均可保持较高的Sb稳定效率;在一定比例BC处理下,修复过程中不同Sb污染程度土壤(G1~G6)中Sb的浸出浓度和有效态含量有所波动,在修复60 d后分别降低了5.89%±3.04%(1.44%~9.08%)和20.49%±17.74%(4.83%~58.39%),而FeS-BC在修复期内均能有效降低Sb浸出浓度和有效态含量,在修复60 d后分别降低了35.80%±13.80%(17.78%~55.05%)和34.84%±2.28%(31.60%~37.64%);FeS-BC材料对土壤中Sb稳定机制包括:静电吸引、离子交换、氧化还原、络合作用和沉淀作用;BC和FeS-BC修复14 d后的不同Sb污染程度土壤(G1~G6)经干湿交替和冻融循环后,BC修复的土壤中Sb浸出液浓度和有效态含量均增加,存在一定释放风险,FeS-BC修复的土壤中Sb浸出液浓度增加而有效态含量降低.To investigate the remediation effects and mechanisms of iron sulfide-modified biochar(FeS-BC)on polluted soil surrounding an antimony smelting plant,soil from around a decommissioned antimony smelting plant in the Qinglong County,Guizhou Province,was used as the research subject.Through soil cultivation experiments,the effects of raw biochar(BC)and iron sulfide-modified biochar(FeS-BC)on the leaching toxicity,bioavailability,and speciation of antimony(Sb)in the soil were compared.The results showed that with an FeS∶BC mass ratio of 1∶5 and an addition rate of 7%,the average stabilization efficiency of Sb in soils with varying degrees of Sb pollution(G1-G6)reached 66.85%.FeS-BC maintained high Sb stabilization efficiency across a wide pH range(2.0-10.0).In soils treated with a certain proportion of BC,the leaching concentration and bioavailable content of Sb fluctuated during the remediation process,decreasing by 5.89%±3.04%(1.44%-9.08%)and 20.49%±17.74%(4.83%-58.39%),respectively,after 60 days of remediation.In contrast,FeS-BC effectively reduced the leaching concentration and bioavailable content of Sb throughout the remediation period,with reductions of 35.80%±13.80%(17.78%-55.05%)and 34.84%±2.28%(31.60%-37.64%),respectively,after 60 days of remediation.The stabilization mechanisms of Sb in soil by FeS-BC included electrostatic attraction,ion exchange,redox reactions,complexation,and precipitation.After 14 days of remediation with BC and FeS-BC,soils with varying Sb pollution levels(G1-G6)were subjected to alternating wet and dry conditions and freeze-thaw cycles.The leachate concentration and bioavailable content of Sb in soils remediated with BC increased,indicating a certain release risk.In contrast,in soils remediated with FeS-BC,while the leachate concentration of Sb increased,the bioavailable content decreased.

关 键 词：锑(Sb) 生物炭 硫化亚铁 土壤修复 稳定机制 

分 类 号：X53[环境科学与工程—环境工程]