Molecular investigation on the desorption process of alkane contaminant from fused silica surface in nonionic surfactant solution

• Published in: Applied surface science Vol. 565; p. 150516
• Main Authors: Shen, Rong-qi, Bai, Qing-shun, Li, Yu-hai, Guo, Yong-bo, Zhang, Peng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2021
• Subjects: Alkane organic film; Desorption; Fused silica; Non-ionic surfactant; Non-ionic surfactant; Desorption; Fused silica; Alkane organic film
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2021.150516

Definition of the hydrated layer. The left of the picture is the atomic configuration of surfactant molecules on the surface of an oil droplet, the right of the picture shows the radial distribution function (RDF) of the oxygen atom in the hydrophilic functional group and water molecules. [Display omitted] •The desorption mechanism of alkane molecules is investigated by MD simulation.•The effects of the surfactant molecular structure are discussed in detail.•The temperature of the surfactant solution on the oil droplet desorption is analyzed.•The effects of surfactant concentration are investigated. In this article, the molecular level investigation on the detachment process of the alkane contaminant from the fused silica surface in nonionic surfactant solution is performed by using molecular dynamics simulation. Three important cleaning parameters including surfactant molecule structure, temperature and surfactant concentration are discussed. We found that the hydrophilic tail of the nonionic surfactant molecule plays a leading role in the desorption process of the oil droplet. The activated chemical activity in surfactant solution with the increasing temperature of solution facilitates the desorption of alkane contaminant. The critical surfactant concentration is vital for cleaning in a real situation. High surfactant concentration can facilitate the desorption of oil droplet in a static solution. The efficiency of water flooding decrease, when the concentration of surfactant is high. Our study can help to understand the cleaning mechanism in surfactant solution and is important for its application in industrial cleaning.