摘要
制备了生物炭负载纳米零价铁(nZVI/BC)复合材料,采用SEM、TEM、FTIR、EDS、XPS等手段对其表面形貌、粒径大小、官能团结构、表面元素及化学形态进行了表征和分析。通过镉(Cd)形态、浸出毒性、生物可利用性、上覆水中溶解态Cd质量浓度及底泥理化性质等指标评价了nZVI/BC对湖泊底泥中Cd的修复效果。结果表明,相比于对照组,经56 d修复后nZVI/BC处理组中Cd的残渣态质量分数增加了29.73%,有效降低了Cd的移动性;Cd的浸出质量浓度从4.65μg·L^(-1)降至0.38μg·L^(-1),Cd的生物可提取态质量浓度从5.08μg·L^(-1)降至2.13μg·L^(-1),其浸出质量浓度和生物可提取态质量浓度分别下降了91.83%和58.07%。同时,经过56 d的修复,nZVI/BC使上覆水中溶解态Cd的质量浓度比对照组降低了67.53%。此外,nZVI/BC的添加提高了底泥的pH和有机质,根据这2个指标的变化进一步分析了nZVI/BC复合材料对Cd的稳定机制。以上研究结果可为重金属污染底泥的修复提供参考。
Biochar-supported nano zero-valent iron(nZVI/BC)composites were prepared,and its surface morphology,particle size,functional group structure,surface elements and chemical morphology were characterized and analyzed by SEM,TEM,FTIR,EDS and XPS.The remediation effect of cadmium(Cd)in lake sediment by nZVI/BC was evaluated by Cd speciation,leaching toxicity,bioavailability,dissolved mass concentration of Cd in overlying water and physical and chemical properties of sediment.The results showed that after 56 d remediation,the residual mass speciation of Cd in nZVI/BC treatment group increased by 29.73%in comparison with the control group,which effectively reduced the mobility of Cd.The Cd leaching mass concentration decreased from 4.65μg·L^(-1)to 0.38μg·L^(-1),and the Cd bioextractable mass concentration decreased from 5.08μg·L^(-1)to 2.13μg·L^(-1),and the leaching mass concentration and bioextractable mass concentration of Cd decreased by 91.83%and 58.07%,respectively.At the same time,after 56 d remediation,nZVI/BC reduced the mass concentration of dissolved Cd in the overlying water by 67.53%in comparison with the control group.Besides,the addition of nZVI/BC increased the pH and organic matter of the sediment.According to the changes of these two indexes,the stability mechanism of nZVI/BC composites to Cd was further analyzed.The above results can provide a reference for remediation of heavy metal contaminated sediment.
作者
李皖瑶
曹珊
朱运龙
李俊
刘虹豆
陈欣雨
徐轶群
薛文静
LI Wanyao;CAO Shan;ZHU Yunlong;LI Jun;LIU Hongdou;CHEN Xinyu;XU Yiqun;XUE Wenjing(College of Environmental Science and Engineering,Yangzhou University,Yangzhou 225009,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2022年第7期2188-2197,共10页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金资助项目(42107415)
江苏省自然科学基金资助项目(BK20210830)
江苏省高校大学生创新创业训练计划项目(202111117041Z)。
关键词
纳米零价铁
生物炭
湖泊底泥
镉形态
污染修复
机制分析
nanoscale zero-valent iron
biochar
lake sediment
cadmium speciation
pollution remediation
mechanism analysis
