Authors

Jian RenFollow

Date of Completion

3-15-2017

Embargo Period

3-15-2018

Keywords

membrane separations; forward osmosis; pressure retarded osmosis; hollow fiber membrane; thin film composite; structure performance relationship; computational fluid dynamics

Major Advisor

Jefferey R. McCutcheon

Associate Advisor

Leslie M. Shor

Associate Advisor

Richard S. Parnas

Associate Advisor

Luyi Sun

Associate Advisor

Douglas H. Adamson

Field of Study

Chemical Engineering

Degree

Doctor of Philosophy

Open Access

Open Access

Abstract

Osmotic processes have been considered sustainable solutions for extracting clean water and concentrating impaired water by forward osmosis (FO) and harvesting the osmotic pressure gradient for power generation via pressure retarded osmosis (PRO). Thin film composite (TFC) membranes are considered a preferred platform for osmotic processes wherein the selective and support layers can be tailored independently for preferred chemistry and structure. Hollow fiber TFC membranes in particular have garnered interests because of their high packing density. In this dissertation study, high performance TFC membranes were designed for applications in osmotic processes. Departing from previous hollow fiber membrane developments that focused on utilizing novel materials and fabrication methods, this dissertation focused on elucidating the fundamental structure-property-performance relationships of TFC hollow fiber membranes for osmotic processes. The impact of support layer structure was studied using lab-made hollow fiber supports. The impact of support surface pore size was systematically investigated using commercial ultrafiltration (UF) platforms. The results demonstrate that TFC hollow fiber FO membranes with excellent performance can be made with intrinsically hydrophilic materials, and can be produced at both lab-scale and module-scale with relative ease using off-the-shelf UF membranes. Finally, to optimize design and operation parameters in the hollow fiber FO process at various scales, a computational fluid dynamics model was developed to elucidate the inextricable link between various parameters and to optimize the design parameters for TFC hollow fiber membranes and modules for osmotic processes.

Download
COinS