Details

Autor(en) / Beteiligte

• Xiao, Minhao

Titel

Tailoring and Characterizing Pore Size Distribution of Phase Inverted Porous Polymeric Membranes: What, Why, and How?

Ort / Verlag

ProQuest Dissertations & Theses

Erscheinungsjahr

2024

Link zum Volltext

Quelle

ProQuest Dissertations & Theses A&I

Beschreibungen/Notizen

• In this thesis, the methodology of tailoring and characterizing pore size distribution (PSD) of phase-inverted porous polymeric membranes is conducted with theoretical model simulations and experimental verification. The investigative journey begins with the revealing of the significance of pore size and pore size distribution for membrane performance with the CFD and other classical model analysis and culminates in the systematic fabrication matrix for membrane pore manipulation, which is strongly supported by precise characterizations and distinguished by the illustration of classical hydrodynamic models.Chapter 2 initiates the effects of PSD mean, shape, and scale on water permeance and solute rejection of membranes by using classical analytical models and computational fluid dynamics (CFD), which elaborates on the importance of precisely manipulating membrane pore size and pore size distribution from a theoretical perspective, emphasizing the need to avoid excessively large or small pores. Chapter 3 systematically examines the influence of polymeric membrane sample preparation techniques on their morphologies and structures as revealed by scanning electron microscopy (SEM) to develop a sample characterization method that not only serves as a guide for accurate SEM characterization of polymeric membranes but also as a stepping stone towards standardizing protocols.Chapter 4 involves the fabrication of porous membranes and integrates the surface porosity characterization via SEM and the data derived from contact angle measurements (with dry-wet adjustment ratio applied in wet conditions), establishing a novel method for quantifying the surface porosity of porous membranes through contact angle measurements. Chapter 5 investigates the water permeability and solute rejection of microfiltration (MF) and ultrafiltration (UF) membranes in pressure-driven filtration by integrating the surface porosity, mean pore size, pore size distribution, and skin layer thickness of dry membrane samples into three classic hydrodynamic pore-flow models (Hagen-Poiseuille (HP), Kozeny-Carman (KC), and Happel’s cell (HC)). The dry-wet ratio, developed in Chapter 4, is conducted to correct and simulate the fully-wetted condition.The culmination of these insights is found in Chapter 6, which presents a series of experimental methods for manipulating membrane pore size and pore size distribution. Here, the superiority of nano-bubble water as a pore former is highlighted, characterized by enhanced water permeance without trading off solute rejection, indicating an innovative approach for fabricating polymeric porous membranes.In summary, this thesis offers accurate and standardized methods for membrane characterizations from a novel and comprehensive perspective. Additionally, it elucidates the significance and provides techniques for precisely tailoring membrane pore size and pore size distribution through simulation models and experimental validation, paving the way for the advancement of mesoporous membrane design for a wide range of academic and industrial applications.