Date of Defense
24-11-2025 12:30 PM
Location
F1-1077
Document Type
Dissertation Defense
Degree Name
Doctor of Philosophy in Chemical Engineering
College
COE
Department
Chemical and Petroleum Engineering
First Advisor
Prof. Nayef Ghasem
Keywords
Carbon dioxide, Functionalized ZnO nanoparticles, Natural gas purification, Gas-Liquid membrane contactor, Composite membrane, Nanofluids, Absorption flux.
Abstract
Natural gas sweetening demands the efficient removal of CO₂ to enhance heating value and prevent equipment corrosion. Gas–liquid membrane contactors (GLMCs) have garnered attention as promising solutions to traditional separation methods due to their modularity, high interfacial area, and energy efficiency. Nonetheless, they suffer from some serious challenges such as membrane wetting, while absorbents either exhibit low absorption capacity or high energy demands and corrosion. This work addresses these limitations through two complementary strategies. In the first, ZnO nanoparticles were hydrophobically functionalised and incorporated into polymer matrices to fabricate composite membranes with superior hydrophobicity and reduced pore wetting. In the second, suitably surface-modified ZnO nanoparticles were dispersed in absorption solvents as nanofluids to intensify gas–liquid mass transfer. The nanofluids were tested in hollow fiber membrane contactors to investigate the solvent-side enhancement. Material characterization confirmed successful modification and stable dispersions. Experimental studies demonstrated that the modified membranes effectively suppressed wetting and achieved higher CO₂ flux, and the nanofluids boosted absorption performance while enabling operation with lower amine concentration. Performance evaluations were carried out to examine the influence of key operating parameters on CO2 absorption performance in both membrane- and solvent-based systems. Together, the dual approach of membrane modification and solvent intensification offers a practical route toward high performance, energy-efficient GLMC systems for CO2 removal from natural gas.
Included in
DEVELOPMENT OF COMPOSITE MEMBRANES AND NANOFLUID ABSORBENTS INCORPORATING SURFACE-FUNCTIONALIZED NANOPARTICLES FOR ENHANCED CO₂ ABSORPTION IN GAS–LIQUID MEMBRANE CONTACTORS
F1-1077
Natural gas sweetening demands the efficient removal of CO₂ to enhance heating value and prevent equipment corrosion. Gas–liquid membrane contactors (GLMCs) have garnered attention as promising solutions to traditional separation methods due to their modularity, high interfacial area, and energy efficiency. Nonetheless, they suffer from some serious challenges such as membrane wetting, while absorbents either exhibit low absorption capacity or high energy demands and corrosion. This work addresses these limitations through two complementary strategies. In the first, ZnO nanoparticles were hydrophobically functionalised and incorporated into polymer matrices to fabricate composite membranes with superior hydrophobicity and reduced pore wetting. In the second, suitably surface-modified ZnO nanoparticles were dispersed in absorption solvents as nanofluids to intensify gas–liquid mass transfer. The nanofluids were tested in hollow fiber membrane contactors to investigate the solvent-side enhancement. Material characterization confirmed successful modification and stable dispersions. Experimental studies demonstrated that the modified membranes effectively suppressed wetting and achieved higher CO₂ flux, and the nanofluids boosted absorption performance while enabling operation with lower amine concentration. Performance evaluations were carried out to examine the influence of key operating parameters on CO2 absorption performance in both membrane- and solvent-based systems. Together, the dual approach of membrane modification and solvent intensification offers a practical route toward high performance, energy-efficient GLMC systems for CO2 removal from natural gas.