Lee Jin Gyun, Larive Luke L, Valsaraj Kalliat T, Bharti Bhuvnesh
Cain Department of Chemical Engineering , Louisiana State University , Baton Rouge , Louisiana 70803 , United States.
ACS Appl Mater Interfaces. 2018 Dec 12;10(49):43282-43289. doi: 10.1021/acsami.8b17748. Epub 2018 Dec 3.
Synthetic amphiphiles used for managing large-scale oil spills have a toxic impact on the environment and marine life. Developing new oil spill recovery technologies is critical to minimize the environmental and ecological impact of such disasters. Here, we show that a mixture of lignin nanoparticles and 1-pentanol forms a biocompatible alternative to nondegradable, synthetic amphiphiles used for oil spill recovery. The pentanol in the mixture generates initial Marangoni flow and confines the spilled oil into a thick slick on the surface of water. While the alcohol solubilizes, lignin nanoparticles irreversibly adsorb onto the oil-water interface. We find that the lignin nanoparticle adsorption to the oil-water interface is governed by a combination of electrostatic, van der Waals, and hydrophobic interactions between the particles and the interface. These interactions, combined with interparticle electrostatic repulsion between nanoparticles adsorbed at the oil-water interface, drive the formation of a submonolayer. The submonolayer transforms into a film of jammed nanoparticles due to compressive stress acting on the interface upon the solubilization of pentanol. This interfacial layer of lignin nanoparticles restricts oil from respreading and locks the oil in its confined state. The herded state of the oil with the interfacial layer of nanoparticles facilitates safe removal of the spilled oil using mechanical methods. The study presents a new principle of using a mixture of heavy alcohol and biocompatible nanoparticles for oil herding applications, thus providing an ecofriendly alternative to oil spill recovery.
用于处理大规模石油泄漏的合成两亲分子对环境和海洋生物具有毒性影响。开发新的石油泄漏回收技术对于将此类灾害对环境和生态的影响降至最低至关重要。在此，我们表明木质素纳米颗粒和1-戊醇的混合物形成了一种生物相容性替代物，可替代用于石油泄漏回收的不可降解合成两亲分子。混合物中的戊醇产生初始的马兰戈尼流，并将泄漏的油限制在水面上形成厚厚的油膜。当醇溶解时，木质素纳米颗粒不可逆地吸附在油水界面上。我们发现木质素纳米颗粒对油水界面的吸附受颗粒与界面之间的静电、范德华力和疏水相互作用的共同作用控制。这些相互作用，再加上吸附在油水界面的纳米颗粒之间的颗粒间静电排斥，驱动形成亚单层。由于戊醇溶解时作用在界面上的压缩应力，亚单层转变为纳米颗粒堵塞的膜。木质素纳米颗粒的这个界面层限制油重新铺展，并将油锁定在其受限状态。油与纳米颗粒界面层的聚集状态便于使用机械方法安全去除泄漏的油。该研究提出了一种使用重醇和生物相容性纳米颗粒混合物进行油聚集应用的新原理，从而为石油泄漏回收提供了一种环保替代方案。
