摘要
生物炭(BC)在修复重金属污染土壤时,其修复效果与制备条件及原材料密切相关。以不同碳化温度(300、500和700℃)的烟秆生物炭BC及其纳米羟基磷灰石(nHAP)改性生物炭(HBC)为研究对象,采用微宇宙培养实验探究不同时段(7、14和30 d)烟秆BC及HBC对矿区Pb、Zn污染土壤的钝化修复效果。结果表明:不同温度的BC和HBC均能增加土壤pH值(7.81~8.56),并分别使土壤Pb毒性浸出浓度显著降低了30.02%~34.75%和28.23%~34.02%,使有效态Pb降低了37.95%~51.71%和22.56%~26.52%,有效态Zn降低了31.90%~55.52%和19.31%~41.70%;Pb、Zn生物有效性在培养7 d时降低最明显,不同BC使土壤Pb、Zn酸溶态降低了8%~11%和6%~14%,同时增加了可还原态、可氧化态和残渣态;而HBC则促使Pb、Zn酸溶态和可还原态向可氧化态和残渣态转化。BC对土壤Pb、Zn修复效果与HBC相当,因此,烟秆BC和HBC在钝化矿区Pb、Zn污染土壤方面具有显著效果,可为矿区土壤污染修复提供科学依据。
Tobacco stem biochar(BC)has been widely used in the remediation of heavy metal-contaminated soil,and its remediation effect is closely related to the preparation conditions and raw materials.Taking tobacco stem-derived biochar(BC)and its nano hydroxyapatite(nHAP)modified biochar(HBC)pyrolyzed at different temperatures(300,500 and 700℃)as research objects,the microcosmic cultivation experiment was used to explore the passivation and remediation effects of tobacco stem BC and HBC on Pb and Zn contaminated soil in mining areas at different periods(7,14 and 30 days).The results showed that BC and HBC prepared at different temperatures could increase soil pH to 7.81-8.56,and significantly reduce the leaching concentration of soil Pb by 30.02%-34.75%and 28.23%-34.02%,respectively;and the soil available Pb decreased by 37.95%-51.71%and 22.56%-26.52%,respectively,while the soil available Zn decreased by 31.90%-55.52%and 19.31%-41.70%,respectively.The bioavailability of Pb and Zn decreased most significantly after 7 days of incubation.Different BC reduced the acid soluble state of Pb and Zn by 8%-11%and 6%-14%,respectively,and meanwhile,increased the reducible state,oxidizable state and residual state of Pb and Zn.HBC,on the other hand,promotes the transformation of acid soluble and reducible Pb and Zn into oxidizable state and residual states.The remediation effect of BC on soil Pb and Zn is equivalent to that of HBC.Therefore,tobacco stem-derived BC and HBC have significant effects in passivating Pb and Zn contaminated soil in mining areas,which can provide scientific basis for soil pollution remediation in mining areas.
作者
胡维
程建中
高维常
涂成龙
唐源
HU Wei;CHENG Jianzhong;GAO Weichang;TU Chenglong;TANG Yuan(School of Public Health,the key laboratory of Environmental Pollution Monitoring and Disease Control,Ministry of Education,Guizhou Medical University;State Key Laboratory of Environmental Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences;Guizhou Academy of Tobacco Science)
出处
《地球与环境》
CAS
CSCD
北大核心
2024年第2期144-153,共10页
Earth and Environment
基金
贵州省科技计划项目(黔科合支撑[2021]一般187、黔科合基础-ZK[2022]重点047)
中国烟草总公司重点研发项目(110202102038)。
关键词
铅锌矿土壤
烟秆生物炭
改性
迁移
化学形态
生物有效性
soils in Pb-Zn mining area
tobacco stem-derived biochar
modification
mobility
geochemical forms
bioavailability
