Colloids and Surfaces A: Physicochemical and Engineering Aspects 615 (2021) 126191 Available online 8 February 2021 0927-7757/© 2021 Elsevier B.V. All rights reserved. An experimental and numerical study of droplet spreading and imbibition on microporous membranes Debanik Bhattacharjee, Hadi Nazaripoor, Babak Soltannia, Md Farhad Ismail, Mohtada Sadrzadeh * Department of Mechanical Engineering, Advanced Water Research Laboratory, University of Alberta, Canada HIGHLIGHTS G R A P H I C A L ABSTRACT • Phenomena of droplet spreading and imbibition on microporous MF mem- branes investigated. • The effective permeability of the mem- brane obtained by validating the nu- merical predictions with contact angle measurements. • A correction factor dependent on the imbibition time scale proposed to bridge the gap between the hydrodynamic and effective permeabilities. A R T I C L E INFO Keywords: Droplet spreading Imbibition Porous media Membranes ABSTRACT Microporous membranes are permeable substrates primarily used for wastewater treatment and desalination. The lab-fabricated and commercial polyethersulfone (PES) microporous membranes are characterized for permeability by fltration test, cross-section thickness by SEM images, surface roughness by AFM data, and hydrophilicity by dynamic contact angle measurements. The choice of membranes of different nominal pore sizes ensures a diverse range of imbibition time scale. The hydrodynamic permeability of these membranes is calculated based on the cross-section thickness and its resistance, which is obtained from fltration test. A lubrication-based mathematical model using precursor flm approximation is used to study the behavior of droplet spreading and imbibition on the membrane surface. The theoretical disjoining pressure is also shown to be related to its numerical value obtained from the mathematical model, in the case of apolar and polar in- teractions. The effective permeability obtained by validating the numerical predictions with contact angle ex- periments, is then matched to hydrodynamic permeability by introduction of lubrication ratio at the equilibrium stage. * Corresponding author. E-mail address: sadrzade@ualberta.ca (M. Sadrzadeh). Contents lists available at ScienceDirect Colloids and Surfaces A: Physicochemical and Engineering Aspects journal homepage: www.elsevier.com/locate/colsurfa https://doi.org/10.1016/j.colsurfa.2021.126191 Received 17 October 2020; Received in revised form 16 January 2021; Accepted 17 January 2021