模板胶束法三维网络纳米复合吸附剂的可控合成及其吸/脱附性能研究

In recent years, the three-dimensional structured nanocomposite hydrogels, with the characteristics of fast and high adsorption, are receiving increasing interests for the treatment of heavy metal pollution. Many types of nanocomposite hydrogels have been developed, but from the practical applications, these hydrogels show poor adsorption selectivity to the heavy metals and lower desorption percentage as a result of their higher affinity to water molecules, by which the reusability of these hydrogels is severely limited. In this project, a series of micelles template-assisted hydrogels will be designed and prepared. Many different surfactants are involved into the three-dimentional networks to construct a novel nanocomposite hydrogel with tailored size. Subsequently, several hydrophobic monomers and nanometer-sized attapulgite are incorporated to make the three-dimensional networks be orderly, and accordingly, a novel, fast-responsive and easy-regenerative adsorbent can be designed and developed. The quantitative structure-activity relationship and the adsorption properties will be investigated in detail. This is helpful for us to reveal the adsorption/desorption mechanisms of the as-prepared hydrogel to the heavy metals, and to have a deep understanding for the relationship between the internal structures, own characteristics and external environments. Heavy metals have posed a direct threat to our living environment and food safety, and this research project will establish the experimental basis for the design and application of this type of nanocomposite adsorbent for the efficient removal and recycle of heavy metals.

近年来，三维网络纳米复合水凝胶因具有吸附速率快和吸附容量高等优点，在重金属污染治理方面成为研究热点。然而在实际应用时，三维网络水凝胶吸附材料因对水分子具有高度亲和性，对金属离子选择吸附性差，且脱附率不高，造成重复使用性能受限。本项目拟采用模板胶束法，通过不同类型表面活性剂，构建三维网络结构尺寸可控的新型纳米复合水凝胶吸附材料。通过引入疏水单体共聚成分构筑更加规整的网络结构；通过引入棒晶束解离的凹凸棒土，设计和合成对重金属离子具有快速响应和易于再生的新型吸附剂材料。通过该类纳米复合吸附材料构效关系与重金属离子吸附行为的研究，探讨纳米复合吸附剂对重金属离子的吸/脱附机理，加深对有机无机纳米复合吸附树脂内部机构、本身特性与外界环境之间相互关系的理解。重金属对人类生存环境和食品安全造成了严重威胁，通过本研究最终为新型吸附剂在重金属离子的高效去除和回收再利用方面奠定实验基础。

近年来，吸附分离技术在重金属的污染治理方面有很大的发展，然而具有高吸附容量和高选择性，且可回收利用重金属的水处理吸附剂研究较少。本项目以乳液为模板在三维网络吸附剂中构筑了多孔结构，并通过用黏土矿物等代替表面活性剂稳定乳液，将纳米凹凸棒石、蒙脱石等无机组分引入到三维网络水凝胶结构中，一步法合成新型的对重金属离子具有选择吸附性和再生性能的新型吸附材料；结合沉淀聚合和双乳液模板，实现了三维网络吸附剂从块状到球形再到微球的转变。通过深入研究模板胶束法形成三维网络纳米复合吸附剂材料的形成机理，理清了胶束模板形成的孔结构与快速吸附之间的关系，分析了纳米分散凹凸棒石对三维网络的规整性及对吸附剂材料重复使用性能的影响，阐明了三维网络吸附剂的结构与吸附性能之间的关系。此外，结合目前吸附剂的研究发展动态，拓展构建了黏土矿物基和木棉纤维基等超强吸附剂，为进一步研究和研制超强吸附剂提供了有益的借鉴，为新型重金属离子回收吸附剂的研制和应用提供了有益的理论指导。