巯基改性苦草生物炭对水中多氯联苯的去除研究  

Removal of polychlorinated biphenyls in water by sulfhydryl modified Vallisneria natans biochar

作　　者：陈刚 曹鎏 孙艳华 蒋娟 鲜啟鸣[2] CHEN Gang;CAO Liu;SUN Yanhua;JIANG Juan;XIAN Qiming(China Southern Power Grid Power Technology Co.,Ltd.,Guangzhou 510080,China;State Key Laboratory of Pollution Control and Resource Reuse,School of Environment,Nanjing University,Nanjing 210023,China;Yinchuan University of Science and Technology,Yinchuan 750021,China)

机构地区：[1]南方电网电力科技股份有限公司,广东广州510080 [2]污染控制与资源化研究国家重点实验室,南京大学环境学院,江苏南京210023 [3]银川科技学院,宁夏银川750021

出　　处：《中国测试》2022年第10期8-15,共8页China Measurement & Test

基　　金：国家重点研发计划课题(2021YFC1809101)。

摘　　要：多氯联苯(PCBs)作为典型的持久性有机物,能够通过食物链进行传递,对生物体和环境安全产生严重威胁。该研究采用水生植物苦草残体进行热解制备生物炭,对其进行巯基改性,通过正交试验优化巯基改性生物炭的制备条件,并探究生物炭对水中PCB-155的去除效果,以及对PCB-155吸附动力学和吸附等温线。同时,采用热重、红外光谱、X射线光电子能谱、比表面积和孔径表征改性前后生物炭的结构、组成及其形貌特征。结果表明,改性后的生物炭巯基负载量约0.6μg/g,对PCB-155去除效果提升10倍以上;改性后的生物炭对PCB-155的吸附符合准一级、准二级和Elovich模型,在25℃和35℃时吸附等温线均符合Freundlich模型。综上,利用巯基改性的苦草生物炭能有效吸附水中PCB-155,为水中多氯联苯的去除提供了新的方法。Polychlorinated biphenyls(PCBs) are persistent organic pollutants that can be transmitted through the food chain and poses a serious threat to the safety of organisms and the environment. In this study, aquatic plant residues of Vallisneria natans was pyrolyzed to prepare biochar and modified with sulfhydryl groups.The preparation method was optimized by orthogonal experiment. The removal rate of PCB-155 in water by the modified biochar was investigated, and the adsorption kinetics and adsorption isotherm of PCB-155 were also studied. Thermogravimetric analysis, infrared spectroscopy, X-ray photoelectron spectroscopy, specific surface area and pore size analysis were used to characterize the structure, composition and morphology of the modified biochar. As a result, 0.6 μg/g sulfhydryl groups were successfully grafted onto the surface of the modified biochar and the removal rate of PCB-155 increased 10 times compared with unmodified biochar. The adsorption kinetics of PCB-155 by the modified biochar conformed to pseudo-first order, pseudo-second order and Elovich models, and the adsorption isotherms fit the Freundlich model at 25 °C and 35 °C, respectively. In conclusion, the sulfhydryl modified biochar of V. natans can be used to adsorb PCB-155 effectively, which might provide a new approach to the removal of polychlorinated biphenyls in water.

关 键 词：多氯联苯 生物炭 巯基改性 吸附 

分 类 号：X832[环境科学与工程—环境工程]