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yes / The non-isothermal kinetic and thermal behaviour of a naturally formed dolomite in conditions that approach in situ CO2 capture in chemical looping reforming, were investigated. The performance of this dolomite was studied at micro-scale in ‘dry’ conditions, as well as at macro-scale in ‘dry’ and ‘wet’ conditions to investigate the effects of scale (3 mg, 2.5 g), partial pressures of CO2 (<15 kPa) and steam, and deactivation upon limited cycling. The carbonation and calcination kinetics were modelled using an improved iterative Coats–Redfern method. Increasing CO2 partial pressures on the ‘dry’ macroscale exacerbated the experimental carbonation conversions in an inversely proportional trend when compared with those at micro-scale. The presence of steam had a positive effect on CO2 chemisorption. Steam had a negligible influence on the calcination activation energies. The activation energies of carbonation were increased for the experiments at the highest CO2 partial pressures under wet conditions.

Inorganic nano- and micromaterials (NMMs) exhibit unique properties including high surface areas, tunable optical and electronic properties, low densities, thermal and chemical robustness, and catalytic capabilities, among others. One of the more novel subclasses of NMMs, metal-organic frameworks (MOFs), are crystalline porous coordination polymers consisting of metal nodes connected by organic linkers to form one-, two-, or three-dimensional frameworks. While the mechanism of MOF formation is complex, tuning the metal:ligand ratios, reaction temperature and vessel pressure, ligand concentration, modulator concentration, and H+ activity impacts particle size, morphology, dispersity, and isotropy of these materials. MOFs also exhibit post-synthetic modification capabilities, which, along with their tunable synthetic nature, make them promising candidates for composite materials such as functionalized nanofillers for reverse osmosis (RO) desalination. The work described herein investigates synthetic parameters of a zirconium-based porphyrinic MOF, PCN-222, to selectively control its crystal size, aspect ratio, and dispersity. Size-constrained PCN-222 was post-synthetically modified with fatty acids and zwitterions to be used as RO thin-film composite (TFC) membranes with improved membrane flux, salt rejection, and anti-fouling properties. The synthetic parameters of MOFs were also considered for the commercial scale-up of CO2 direct air capture (DAC) solid sorbents, including UiO-66, MIL-101-Cr, and Mg-MOF-74, to preserve CO2 uptake capacities between lab and industrial scales. / Doctor of Philosophy / Metal-organic frameworks (MOFs) are unique, highly porous materials that have garnered attention for their potential in many applications, including catalysis, drug delivery, energy, and gas storage. In this work, MOFs were produced for environmental applications, particularly for the conversion of salt water to drinkable water in a process known as reverse osmosis (RO) desalination. RO uses a thin membrane to separate dissolved salt, as well as organic materials such as decomposed organisms, from water. Though RO membranes are widely used commercially, they suffer from high costs and short lifetimes; however, their performance is improved through the incorporation of extremely small materials known as nanoparticles. MOF nanoparticles were grown small enough to be dispersed in the polymer matrix of the thin membrane, then functionalized to improve salt rejection and flux, or the speed at which clean water is produced from RO processes. They were also modified to improve lifetimes by preventing the build-up of organic materials on the surface. Besides clean water, MOFs were also prepared for capturing the greenhouse gas, CO2, directly from the air. Because MOFs can be made with many different functionalities, they are promising materials for many different research fields.

<p dir="ltr">This thesis investigates entrainment phenomena across multiple spatial scales, focusing on two distinct but interconnected applications: respiratory droplet transport in cough jets and CO$_2$ mixing in wind turbine wakes. Through comprehensive experimental approaches, this research advances our understanding of how entrainment processes govern fluid transport across these scales while contributing to solutions for pressing environmental and public health challenges.</p><p dir="ltr">The first study develops and validates a novel cough simulator for respiratory disease research. Using a subwoofer-driven aerosol chamber controlled by a modified gamma-probability-distribution function, the device generates pulsatile airflow that accurately mimics human coughs. Extensive particle image velocimetry and flow visualization measurements demonstrate the simulator's capability to produce repeatable cough profiles with peak velocities ranging from 2.99 to 38.47 m/s and peak velocity times from 8.75 to 60.00 ms. The device's innovative design offers precise control over key flow parameters while maintaining accessibility through the use of off-the-shelf components.</p><p dir="ltr">The second study examines entrainment effects in wind turbine wakes through wind tunnel experiments investigating CO$_2$ transport. Using a scaled wind turbine model and spatial CO$_2$ concentration measurements, this work provides experimental validation of computational predictions regarding turbine-induced mixing. Experiments conducted at two free-stream velocities (4 m/s and 10 m/s) reveal significant differences in CO$_2$ concentration profiles between cases with and without the turbine present, particularly in the near-wake region where turbine-induced mixing most strongly influences vertical redistribution of CO$_2$. </p><p dir="ltr">This research demonstrates how careful experimental characterization can illuminate entrainment mechanisms from micro-scale droplet transport to macro-scale atmospheric mixing, while providing practical applications for addressing contemporary challenges in disease transmission and atmospheric transport processes. The findings contribute to both fundamental fluid dynamics understanding and applied solutions for public health and environmental management.</p>

Yes / A mass transfer model was developed for CO2 capture from a binary gas mixture of N2/CO2 in hollow fibre membrane contactors under laminar flow conditions. The axial and radial diffusions through membrane and convection in tube and shell sides with chemical reaction were investigated. COMSOL software was used to numerically solve a system of non-linear equations with boundary conditions by use of the finite element method. Three different amine solutions of monoethanolamine (MEA), diethanolamine (DEA) and n-methyldiethanolamine (MDEA) were chosen as absorbent in lumen to consider the mass transfer rate of CO2 and compare their removal efficiency. The modelling results were compared with experimental data available in the literature and a good agreement was observed. The CFD results revealed that MEA had the best performance for CO2 removal as compared to DEA and MDEA under various operating conditions due to the different CO2 loading factor of absorbents. Furthermore, efficiency of CO2 removal was highly dependent on the absorbent concentration and its flow rate, increasing of the gas flow rate caused a reduction in gas residence time in the shell and consequently declined CO2 mass transfer. The modelling results showed the influence of the absorbent concentration on the CO2 mass transfer has improved due to availability of absorbent reactants at the gas-liquid interface.