Effect of a cationic surfactant on the volatilization of PAHs from soil
Effect of a cationic surfactant on the volatilization of PAHs from soil
复制标题
阳离子表面活性剂对土壤PAHs挥发的影响
DOI：
10.1007/s11356-011-0631-0
复制
发表时间：
2012-06-01
影响因子：
5.8
通讯作者：
Zhu, Lizhong
中科院分区：
文献类型：
--
作者：
Lu, Li;Zhu, Lizhong
目的阳离子表面活性剂在土壤中很常见，因为它们在日常化妆品和清洁产品中使用，因此它们作为土壤改良剂已被提出用于缓解和修复有机污染土壤。这类表面活性剂可能会影响有机污染物在环境中的转移和去向。研究了阳离子表面活性剂溴化十二烷基吡啶(DDPB)对水稻土中多环芳烃(PAHs)挥发的影响。材料与方法在开放式系统中测试了不同浓度的DDPB对湿润土壤中多环芳烃的挥发。用顶空气相法分别研究了DDPB对封闭体系中多环芳烃的气液平衡和固-汽相平衡的影响。结果和讨论DDPB对土壤中多环芳烃的气液和固-气过程均有影响。当DDPB浓度低于临界胶束浓度(CMC)时，多环芳烃与吸附在气液界面上的表面活性单体相互作用，促进多环芳烃从溶液中挥发，促进多环芳烃从本体溶液向气液界面的迁移。但当DDPB大于CMC时，由于胶束对多环芳烃的增溶作用，挥发受到抑制。吸附表面活性剂的形成显著抑制了土壤中多环芳烃的固-气挥发。结论DDPB对土壤中多环芳烃的挥发损失减少是其对气液和固-气过程的综合作用。水分含量较低的土壤对多环芳烃挥发的抑制作用更为明显。
Purpose Cationic surfactants are common in soils because of their use in daily cosmetic and cleaning products, and their use as a soil amendment for the mitigation and remediation of organic contaminated soils has been proposed. Such surfactant may affect the transfer and fate of organic contaminants in the environment. This study investigated the effect of a cationic surfactant, dodecylpyridinium bromide (DDPB), on the volatilization of polycyclic aromatic hydrocarbons (PAHs) from a paddy soil.Materials and methods The volatilization of PAHs from moist soil amended with different concentrations of DDPB was tested in an open system. The specific effects of DDPB on the liquid-vapor and solid-vapor equilibriums of PAHs were separately investigated in closed systems by headspace analysis.Results and discussion DDPB affects both liquid-vapor and solid-vapor processes of PAHs in soil. At DDPB concentrations below the critical micelle concentration (CMC), movement of PAHs from the bulk solution to the gas-liquid interface appeared to be facilitated by interaction between PAHs and the surfactant monomers adsorbed at the gas-liquid interface, promoting the volatilization of PAHs from solution. However, when DDPB was greater than the CMC, volatilization was inhibited due to the solubilization of PAHs by micelles. On the other hand, the formation of sorbed surfactant significantly inhibited the solid-vapor volatilization of PAHs.Conclusions The overall effect of the two simultaneous effects of DDPB on liquid-vapor and solid-vapor processes was a decreased volatilization loss of PAHs from soil. Inhibition of PAH volatilization was more significant for the soil with a lower moisture content.