材料表面气泡对水中全氟表面活性剂吸附的影响及作用机制

材料表面普遍存在气泡而吸附研究中几乎都忽略了这些气泡对污染物吸附的影响，特别是全氟表面活性剂（PS）容易富集到气泡表面，势必会影响其界面吸附特性，这可能是揭示PS有别于碳氢化合物吸附机理的关键。本项目拟通过不同脱气方法系统研究气泡对典型碳基材料、无机颗粒和聚合物有机材料吸附全氟磺酸和全氟羧酸类PS的影响，同时比较气泡对碳氢表面活性剂的影响区别，阐明气泡对PS的影响规律；直接观测材料表面气泡的形貌和分布特征，理论计算PS在气泡界面上的分布状况及气泡吸附对PS总吸附的贡献；实验验证PS的C-F链的疏水疏油性，提出C-F链的疏油性阻止PS吸附到疏水材料上，肃清PS与碳氢化合物有相同的“疏水作用”的模糊认识；提出典型PS在不同材料上的吸附机制，重点阐明基于材料表面气泡的吸附机理。本研究能从本质上认识PS在固液界面的吸附特异性，为吸附技术去除水中的PS以及PS在水环境中的迁移和归趋提供理论支持。

Air bubbles are commonly present on material surfaces, but the adsorption of pollutants by these air bubbles are almost overlooked, and especially the perfluorinated surfactants (PS) are easily concentrated on the surface of air bubbles, which would definitely affect their interfacial adsorption behaviors. This is critical to find the difference of adsorption mechanism between hydrocarbon and PS. This project will fully investigate the effect of air bubbles on the adsorption of PS (perfluorinated carboxylates and perfluorinated sulfonates) on the typical carbon-based materials, inorganic particles, and organic polymer materials via the different degassing methods, and compare difference for the effect of air bubbles on hydrocarbon surfactants and illuminate the effect of air bubbles on PS; Observe the morphologies and distribution of air bubbles on surface surfaces, and theoretically calculate the distribution of PS on air bubbles as well as the contribution of air bubbles adsorption to overall PS adsorption; experimentally verify the hydrophobicity and oleophobicity of C-F chain in PS, and propose that the oleophobicity of C-F chain prevents PS adsorption on hydrophobic material surfaces, preventing the unclear understanding of the same hydrophobic interaction like hydrocarbon compounds; propose the adsorption mechanism of typical PS on different materials, and emphasize on the adsorption mechanism based on the air bubbles on material surfaces. This research would essentially discover the specific adsorption of PS on solid-liquid interfaces, providing theoretical support for the transport and fate of PS in aquatic environments and removal of PS from water using adsorption technology.