Gomes Helena I, Dias-Ferreira Celia, Ottosen Lisbeth M, Ribeiro Alexandra B
CENSE - Center for Environmental and Sustainability Research, Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal; CERNAS - Research Center for Natural Resources, Environment and Society, Escola Superior Agraria de Coimbra, Instituto Politecnico de Coimbra, Bencanta, 3045-601 Coimbra, Portugal; Department of Civil Engineering, Technical University of Denmark, Brovej, Building 118, DK 2800 Kgs. Lyngby, Denmark.
CERNAS - Research Center for Natural Resources, Environment and Society, Escola Superior Agraria de Coimbra, Instituto Politecnico de Coimbra, Bencanta, 3045-601 Coimbra, Portugal.
J Colloid Interface Sci. 2014 Nov 1;433:189-195. doi: 10.1016/j.jcis.2014.07.022. Epub 2014 Aug 1.
Polychlorinated biphenyls (PCB) are persistent organic pollutants (POP) that strongly adsorb in soils and sediments. There is a need to develop new and cost-effective solutions for the remediation of PCB contaminated soils. The suspended electrodialytic remediation combined with zero valent iron nanoparticles (nZVI) could be a competitive alternative to the commonly adapted solutions of incineration or landfilling. Surfactants can enhance the PCB desorption, dechlorination, and the contaminated soil cleanup. In this work, two different surfactants (saponin and Tween 80) were tested to enhance PCB desorption and removal from a soil sampled at a polluted site, in a two-compartment cell where the soil was stirred in a slurry with 1% surfactant, 10mL of nZVI commercial suspension, and a voltage gradient of 1Vcm(-1). The highest PCB removal was obtained with saponin. Higher chlorinated PCB congeners (penta, hexa, hepta and octachlorobiphenyl) showed removal percentages between 9% and 96%, and the congeners with highest removal were PCB138, PCB153 and PCB180. The use of low level direct current enhanced PCB removal, especially with saponin. Electrodechlorination of PCB with surfactants and nZVI showed encouraging tendencies and a base is thus formed for further optimization towards a new method for remediation of PCB polluted soils.
多氯联苯（PCB）是一类持久性有机污染物（POP），在土壤和沉积物中具有很强的吸附性。因此，需要开发新的、具有成本效益的解决方案来修复受PCB污染的土壤。悬浮电渗析修复技术结合零价铁纳米颗粒（nZVI）可能是一种比常用的焚烧或填埋解决方案更具竞争力的替代方案。表面活性剂可以增强PCB的解吸、脱氯以及受污染土壤的清理效果。在这项研究中，测试了两种不同的表面活性剂（皂苷和吐温80），以增强从污染场地采集的土壤中PCB的解吸和去除效果。实验在一个两室电解槽中进行，将土壤与1%的表面活性剂、10mL的nZVI商业悬浮液混合成泥浆并搅拌，施加1Vcm(-1)的电压梯度。使用皂苷时获得了最高的PCB去除率。高氯代PCB同系物（五氯、六氯、七氯和八氯联苯）的去除率在9%至96%之间，去除率最高的同系物是PCB138、PCB153和PCB180。施加低水平直流电增强了PCB的去除效果，尤其是使用皂苷时。表面活性剂和nZVI对PCB的电极脱氯显示出令人鼓舞的趋势，从而为进一步优化形成一种新的PCB污染土壤修复方法奠定了基础。
