pH 诱导分离稠环芳烃高效淋洗剂的设计合成与功能调控机理

Aiming at solving the problems such as poor removal efficiency of the present surfactant for the polycyclic aromatic hydrocarbons, and inseparable of the surfactant and the polycyclic aromatic hydrocarbons in the eluent, a novel eluting agent having high efficiency for the polycyclic aromatic hydrocarbons based on the pH induced separation will design and prepare by introducing aromatic ring and anionic group onto polyamine. By using of π-π interaction between aromatic ring and polycyclic aromatic hydrocarbons, the high removal efficiency for the polycyclic aromatic hydrocarbons can be achieved by adjusted the structure combination of the aromatic ring. Taking advantage of pH responsivity of the polyampholyte, by controlling the molar ratio of the anionic and cationic group, the eluting agent and polycyclic aromatic hydrocarbons can be separated by controlling the pH value. Density functional theory , Henderson-Hasselbalch equation and HLB value will be employed to study the mechanism of the interaction and pH induced separation between the structures of the eluting agent to the polycyclic aromatic hydrocarbons. The relationship between the molecular structure and functional regulation will be established. The research findings of this project will have the important significance on elucidating the high efficient mechanism for the polycyclic aromatic hydrocarbons and revealing the induced separated rules of the polycyclic aromatic hydrocarbons, which will lay a solid foundation for the preparation of the separable and high performance eluting agent and its environment-friendly application in the field of the soil.

针对现有表面活性剂对土壤中稠环芳烃去除效果差，稠环芳烃和表面活性剂难以从淋洗废液中分离等问题，本项目通过在多胺大分子中引入芳环和阴离子基团，设计合成一类通过pH调控可诱导分离的新型高效稠环芳烃淋洗剂。利用芳环与稠环间的π-π作用，通过调配芳环结构增加新型淋洗剂与稠环芳烃之间的相互作用，达到对稠环芳烃的高效去除效率；利用聚两性电解质的pH刺激响应特性，通过调控阴阳离子基团配比，使稠环芳烃和淋洗剂经pH诱导而分离出体系，并实现淋洗剂的回收和循环使用。采用密度泛函理论、Henderson-Hasselbalch方程和HLB值计算，研究新型淋洗剂分子结构与稠环芳烃的作用机理和pH诱导分离机理，建立分子结构调配与功能调控之间的关联。项目研究成果对阐明稠环芳烃的高效去除机理，揭示稠环芳烃的诱导分离调控规律具有重要意义，从而为可分离、高性能稠环芳烃淋洗剂的制备及其在土壤介质中的环境友好应用奠定基础。

本项目主要研究了3个系列共12支具有新颖结构的pH诱导分离新型高效PAHs淋洗剂的设计、合成与应用，明确了分子结构与性能之间的构效关系，阐明了结构调配和功能调控之间的关联和规律。其中，以磺化壳聚糖为主链制备了新型淋洗剂9支CSPAHs1~ CSPAHs9，产率91%以上；以聚乙烯胺为主链制备了新型淋洗剂3支CSPAHs10~ CSPAHs12，产率90%以上。所制备的新型淋洗剂分子的CMC低至3.1×10-3 g/L，通过调控阴阳离子基团比例可调控其等电点，实现该类新型淋洗剂的pH诱导分离。通过Henderson-Hasselbach方程对其随着pH环境的解离情况进行了研究，当pH值>11.5时，可实现淋洗剂分子离子基团的完全解离，阴阳离子基团的解离程度与取代度的关系不大。将所设计合成的新型淋洗剂用于对喹吖啶酮的分散研究，结果表明淋洗剂分子对稠环芳烃类物质具有高π-π和疏水性相互作用，且可实现在pH>8时和pH<5.5时的pH诱导分离功能调控。以人工模拟菲污染土壤，该类淋洗剂对菲的去除率达到91%以上，且淋洗剂可实现回收，回收率达到90%以上。项目执行期间发表论文8篇，其中SCI收录3篇，EI收录1篇，CSCD收录1篇，申请国家发明专利3项，授权2项。通过本项目的研究，为可分离、高性能稠环芳烃淋洗剂的分子结构设计及环境友好应用奠定了良好的理论和实践基础。