Comparison of Capillary Flow Porometry (CFP) and Liquid Extrusion Porometry (LEP) Techniques for the Characterization of Porous and Face Mask Membranes

Abstract

This work aims to study the characterization of several membrane filters by using capillary flow porometry (CFP) and liquid extrusion porometry (LEP) to obtain their pore size distributions (PSD) and mean pore diameters (davg). Three polymeric membranes of different materials namely, polyethylene (PET), cellulose nitrate (CN), and FM (face mask), and one inorganic (namely, alumina Al2O3) from ultrafiltration (UF)/microfiltration (MF) and particle separation were analyzed using a pressure constant fluid/liquid extrusion porometer, developed at institute de la filtration et techniques séparatives (IFTS). Several porosimetric fluids have been used to wet and penetrate into the porous/fiber structure. The results show the accuracy of the setup on characterizing membranes in the UF/MF range by CFP, with reasonable agreement with nominal data of the filters. Additionally, LEP extension of the equipment obtained good agreement with nominal data and the CFP results, while filters presenting a microstructure of highly interconnected pores (face mask) resulted in clear differences in terms of resulting PSD and average sizes when CFP and LEP results are compared.

Face Mask Wastes as Cementitious Materials: A Possible Solution to a Big Concern

“…In [27], the pore structure of the surgical mask was investigated after treatment with ethyl alcohol, UV light, steam, or a washing machine. Peinador et al [28] used capillary flow and liquid extrusion porometry to characterize pore size distributions. Scarce studies have arisen concerning recycling used masks.…”

Non-Destructive Characterization of Industrial Membrane Cartridges by Using Liquid–Liquid Displacement Porosimetry (LLDP)

“…For GLDP runs, the filter media must be previously wet in an appropriated liquid (wetting phase). Perfluoro halogenated compounds are the most successful liquids that meet requirements of complete wettability, low surface tension, low vapor pressures, and low reactivity [19], and accordingly, most GLDP manufacturers usually supply these liquids to their customers (e.g., Porofil ® , Silwick ® , Porewick ® , Galwick ® , with the latest based on different configurations of Fluorinert ® ) [12]. In this study, the wetting liquid was fluorocarboned commercial liquid Fluorinert FC-43 (3M ® ), having a surface tension value of 16 mN/m.…”

“…This characterization comprises the determination of a number of parameters, among which can be included pore size, molecular weight cut-off (MWCO), fractional efficiency, porosity, thickness, permeability, hydrophobicity/hydrophilicity, adsorption, crystallization, tensile and mechanical properties, etc. In terms of pore size, the most complete information comes from determination of the (average) pore size diameter and the pore size distribution (PSD) [12]. There are many characterization methods able to supply the PSD of a membrane, and those can be classified into two main groups: direct [13,14] and indirect [15][16][17][18] methods [19].…”

“…Usually, MF membranes are characterized in terms of mean pore size (in fact, pore diameter) or PSD [20]. For such membranes, the mostly used characterization method (and recommended standard [18]) is the gas-liquid displacement porosimetry (GLDP), also known as capillary flow porometry (CFP) [12].…”

Characterization of Commercial Gas Diffusion Layers (GDL) by Liquid Extrusion Porometry (LEP) and Gas Liquid Displacement Porometry (GLDP)

“…The ratio of hydrophobic and hydrophilic pores could be characterized by using a combination of the results from Capillary Flow Porometry (CFP), Hg intrusion Porosimetry (HgP), and water intrusion porosimetry [39].…”