Microscopic insights into the intensification effect of shear fields on molecular transport across interfaces. (6th April 2020)

• Record Type: Journal Article
• Authors: Yu, Hongping; Song, Xianyu; Luo, Jianhui; Zhao, Guolin; Bao, Bo; Peng, Baoliang; Zhao, Shuangliang
• Is Part Of: Chemical engineering science. Volume 215(2020)
• Publication Date: 2020-04-06
• Subjects: Solute transport -- Interface -- Shear field -- Surfactant -- Dissipative Particle Dynamics; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2019.115381
• Languages: English
• ISSNs: 0009-2509

Abstract

Highlights: Molecular transfer across oil-water interface under shear field is investigated. Addition of different surfactants at various concentrations is considered. Simulations are conducted by means of dissipative particle dynamics method. Microscopic mechanism of shear field enhancing molecular transfer is unraveled. Abstract: Shear field is widely applied to intensify interfacial molecular transport in many chemical engineering processes, and the intensification effect is generally ascribed to the significant increase of contact area between two immiscible liquid phases. Herein, by investigating molecular transport across water-benzene interfaces under different shear fields as a representative study, we show that the interfacial molecular transport per unit area of the interface can be also enhanced by shear field when surfactants are introduced. The microscopic mechanism towards the latter effect is extensively explored by means of Dissipative Particle Dynamics simulation at various shear rates (0–0.3 ps −1 ) and surfactant volume fractions (0–7.1%), and we find that shear flows inhibit the accumulation of surfactants at the interface, and align the remained surfactants along the direction of mass transport, thus enhancing the molecular transfer across the interface. This work provides a microscopic insight into the regulation of interfacial transport with shear flow.