Effect of soil components on the surfactant-enhanced soil sorption of PAHs
Effect of soil components on the surfactant-enhanced soil sorption of PAHs
复制标题
土壤成分对表面活性剂增强土壤对 PAHs 吸附的影响
DOI：
10.1007/s11368-011-0432-6
复制
发表时间：
2012-02-01
影响因子：
3.6
通讯作者：
Zhu, Lizhong
中科院分区：
文献类型：
--
作者：
Lu, Li;Zhu, Lizhong
目的提出使用阳离子表面活性剂来增强疏水性有机污染物（HOCs）的土壤保留。然而，由于土壤组成的复杂性，阳离子表面活性剂对HOCs的土壤吸附的影响仅限于定性的理解。为了进一步了解表面活性剂的作用机理并预测其作用效果，采用间歇平衡法研究了阳离子表面活性剂在5种典型土壤组分上对多环芳烃（PAHs）的吸附，并比较了表面活性剂在5种典型土壤组分上对PAHs的吸附能力。腐殖酸（HA）和石英分别被选为有机质和砂的代表。结果与讨论不同土壤组分对阳离子表面活性剂的吸附量存在较大差异，不同组分对阳离子表面活性剂的吸附量也存在较大差异。除了粘土矿物，HA是一个非常活跃的吸附剂的阳离子表面活性剂，吸附机制包括吸附和分配的过程。对于每一种纯土组分和某一种PAH，均发现了一个分段函数，它可以描述表面活性剂归一化的PAH分配系数Ksf与表面活性剂在固体Qe-DDPB上的吸附量之间的关系（R> 0.9）。结果表明，不同土壤组分对多环芳烃的吸附量随表面活性剂负荷的增加而增加，但在预测阳离子表面活性剂在土壤中的吸附量时，不能忽略HA等土壤有机质的影响。表面活性剂在HA和粘土矿物上的吸附对PAH的分配能力有很大差异。然而，对于每个纯土壤组分，theKsf值是具体相关的表面活性剂负载，这提供了一个可能的手段来预测阳离子表面活性剂在增强吸附的多环芳烃到土壤上的效率。
PurposeThe use of cationic surfactants was proposed to enhance the soil retention of hydrophobic organic contaminants (HOCs). However, due to the complexity of soil composition, the effect of cationic surfactants on the soil sorption of HOCs was limited to a qualitative understanding. To gain further insight into the mechanism of the surfactant and predict its efficiency, a comparative study on the HOCs sorption capacities of the surfactants sorbed on pure typical soil components was investigated.Materials and methodsThe sorption of cationic surfactant onto five pure typical soil components and the sorption of polycyclic aromatic hydrocarbons (PAHs) by the sorbed surfactant were conducted using batch equilibration methods. Humic acid (HA) and quartz were chosen as the representatives of organic matter and sand, respectively. Montmorillonite, kaolinite, and illite were chosen as representatives of clay minerals.Results and discussionThe cationic surfactant sorption capacities of different soil components were of great difference, and the PAH sorption capacities of the surfactant sorbed onto different components were also very different. Aside from the clay minerals, HA was a very active adsorbent for the cationic surfactant, and the sorption mechanism included both adsorption and partition-like processes. For each pure soil component and a certain PAH, a proximately piecewise function was found to describe the relationship of surfactant-normalized PAH distribution coefficientKsfand the sorption amount of the surfactant on solidQe-DDPB(R> 0.9). As a result, the sorption of PAHs by different soil components with certain surfactant loading can be estimated.ConclusionsThe effect of soil organic matter such as HA could not be ignored when predicting the soil sorption of cationic surfactants. The PAH partition capacities of the sorbed surfactant on HA or clay minerals were very different. However, for each pure soil component, theKsfvalue was specifically related with the surfactant loading, which provided a possible means of predicting the efficiency of the cationic surfactant in enhancing the sorption of PAHs onto soils.