In order to develop a new approach to carbon capture using carbonate brines and solid acids, this research project begins the development of a theoretical basis for solid acid based capture systems and experimental work to test the validity of the theory. It appears that solid acids behave like weak acids and are able to increase the concentration of carbon dioxide above a solution compared to what would be achievable without solid acids. Experimental work aimed to show that solid acids behave as indicated by theory. Experiments partially validated the theory through demonstrating desorption of carbon dioxide from a carbonate brine. The regeneration of the solid acid with the help of a strong acid was only partially successful due to instability of the solid acid in the presence of a strong acid. The experimental work used activated.

The properties of block polymers (BPs) are intricately coupled to the dynamic and rich nature of the nanostructured assemblies which result from the phase separation between blocks. The introduction of strong secondary forces, such as electrostatics and hydrogen bonding, into block polymers greatly influences their self-assembly behavior, and therefore affects their physical and electrochemical properties often in non-trivial ways. The recent surge of work expanding scientific understanding of complex spherical packing in block polymers (BPs) has unlocked new design space for the development of advanced soft materials. The continuous matrix phase which percolates throughout spherical morphologies is ideal for many applications involving transport of ions or other small molecules. Thus, determining the accessible parameter range of such morphologies is desirable. Bulk zwitterion-containing BPs hold great potential within the realm of electroactive materials while remaining relatively untapped. In this work, architecturally and compositionally asymmetric diblock polymers were prepared with the majority block having zwitterions tethered to side chain termini at different ratios. Thermally reversible Frank-Kasper phases are observed in multiple samples with significant signs of kinetic arrest and influence. The kinetic influences are validated and described by the temperature-dependent static permittivity. Polyzwitterions combine the attractive features of zwitterions with the mechanical support and processability of polymeric materials. Among these attractive features is a potential for superior permittivity which is limited by the propensity of zwitterions to pack into strongly associating structures. Block polymer self-assembly embodies a plethora of packing frustration opportunities for optimizing polyzwitterion permittivity. The capabilities of this novel approach are revealed here, where the permittivity of a polyzwitterionic block is enhanced to a level comparable to that of pure liquid zwitterions near room temperature (εs ~ 250), but with less than a third the zwitterion concentration. The mechanistic source of permittivity enhancement from a single zwitterion-tethered block polymer is realized deductively through a series of thermal pathways and control sample experiments. Tethered zwitterions within the mixed block interface are frustrated when subject to segmental segregation under sufficient interfacial tension and packing while non-interfacial zwitterions contribute very little to permittivity, highlighting the potential for improvement by several fold.

As society moves to reduce the effects of climate change, there is a growing needfor the use of polymer science in technologies to mitigate the emission of carbon dioxide. Networks containing quaternary ammonium groups with corresponding HCO3 ions providing the mobile counter-charge in the networks have been reported to capture carbon dioxide directly from the atmosphere through a moisture swing mechanism, among other mechanisms. In this work, microstructural analysis of synthesized polystyrene-based anion exchange networks is conducted using known characterization techniques to better understand if variations in sorbent microstructure adjust the distances between the quaternary ammonium groups. Additional surface morphology studies of these sorbents are conducted. X-Ray Diffraction (XRD) spectra reveal the amorphous structure of these polymers and the ability to adjust the distance between quaternary ammonium groups by introducing different spacer groups and various anions into the networks, which may affect the spontaneity of the CO2 to chemisorb to these sorbents. However, Wide Angle X-Ray Scattering (WAXS) conflicts with the XRD data, indicating a change in distance between these groups is not achieved. Additionally, WAXS data indicates an ability to increase the homogeneity of structure in these materials by introducing larger counterions into the networks. Small Angle X-Ray Scattering (SAXS) reveals no obvious large morphological features in these sorbents, which is supported by Scanning Electron Microscopy (SEM) images. In conclusion, XRD and WAXS experiments exhibit conflicting data regarding the ability to adjust the distances between the quaternary ammonium groups in these networks. Proposed actions to resolve this conflict are presented. Finally, SEM sheds light on particle size and morphological features of these materials.

Additive manufacturing, also known as 3D printing, has revolutionized modern manufacturing in several key areas: complex geometry fabrication, rapid prototyping and iteration, customization and personalization, reduced material waste, supply chain flexibility, complex assemblies and consolidated parts, and material innovation. As the technology continues to evolve, its impact on manufacturing is expected to grow, driving further innovation and reshaping traditional production processes. Some innovation examples in this field are inspired by natural or bio-systems, such as honeycomb structures for internal morphological control to increase strength, bio-mimetic composites for scaffold structures, or shape memory materials in 4D printing for targeted drug delivery. However, the technology is limited by its ability to manipulate multiple materials, especially tuning their submicron characteristics when they show non-compatible chemical or physical features. For example, the deposition and patterning of nanoparticles with different dimensions have seen little success, except in highly precise and slow 3D printing processes like aerojet or electrohydrodynamic. Taking inspiration from the layered patterns and structures found in nature, this research aims to demonstrate the development and versatility of a newly developed ink-based composite 3D printing mechanism called multiphase direct ink writing (MDIW). The MDIW is a multi-materials extrusion system, with a unique nozzle design that can accommodate two immiscible and non-compatible polymer or nano-composite solutions as feedstock. The intricate internal structure of the nozzle enables the rearrangement of the feedstock in alternating layers (i.e., ABAB...) and multiplied within each printed line. This research will first highlight the design and development of the MDIW 3D printing mechanism, followed by laminate processing to establish the requirements of layer formation in the XY-axis and the effect of layer formation on its microstructural and mechanical properties. Next, the versatility of the mechanism is also shown through the one-step fabrication of shape memory polymers with dual stimuli responsiveness, highlighting the 4D printing capabilities. Moreover, the MDIW's capability of dual nanoparticle patterning for manufacturing multi-functional carbon-carbon composites will be highlighted. Comprehensive and in-depth studies are conducted to investigate the morphology-structure-property relationships, demonstrating potential applications in structural engineering, smart and intelligent devices, miniature robotics, and high-temperature systems.

The ironmaking process involves the removal of oxygen atoms from the iron oxides to produce iron. Currently, the coal/coke-based blast furnace process dominates the industry with a 71% share of global steel production, making it responsible for 25% of total global industrial CO2 emissions. Several processes have been commercialized to reduce these CO2 emissions such as the direct reduction process which utilizes natural gas for energy and reducing agent. In the last few decades, H2 has been identified as an alternative reducing agent in place of coal and reformed natural gas for decarbonizing the ironmaking process.To commercialize the H2 direct reduction (H2DR) process, it is necessary to study this process on a laboratory, pilot, and industrial scale to identify and address the roadblocks in the path of commercialization. Based on the literature review performed in this dissertation, four knowledge gaps were identified, and hypotheses were formulated to address the same. First, a numerical model was developed for a single iron ore pellet reduction process with a dynamic porosity function, and it was validated using experiments. Second, the equation of the radius of pellet was derived as a function of the degree of reduction using experimental data to account for the shrinking and swelling. Third, a numerical model was developed for a pilot scale H2DR reactor and was validated for average metallization of the pellets at the reactor outlet and the internal temperature profile in the reduction zone. Fourth, the numerical model for the pilot scale H2DR reactor showed a gradient of metallization at the outlet boundary which was validated by experimental metallization analysis of 31 randomly selected pellet samples one by one. At the end of the dissertation, the pilot scale model of the H2DR reactor was scaled up to an industrial scale with a DRI production capacity of 2.38 million tons/year approximately. The mass balance obtained from the industrial scale model was used to perform the techno-economic analysis to determine the economic implications of shifting from a 100% natural gas operation to a 100% H2 operation on an industrial scale.

Electrospun fibrous membranes have gained increasing interest in membrane filtration applications due to their high surface area and porosity. To develop a high-performance water filtration membrane a novel zwitterionic functionalized zwitterionic Polysulfone was Electrospun to bead free fibers on Polysulfone membranes. The SBAES25 was successfully Electrospun on Polysulfone membrane and thermal pressed at above Tg to improve the properties of membrane. The aim of this work is to study Electrospun zwitterionic Polysulfone nanofiber membrane with different characterization methods. The electrospinning method was studied using different polymer concentrations and electrospinning conditions. Scanning Electron Microscopy was used to study the porosity and diameter size of the fiber. TGA-ASSAY method was used to study the difference in water uptake ratio of Polysulfone membrane with and without the Electrospun fiber. A goniometer was used to test the water contact angle of the membrane. Tensile tests were performed to study the improvements in mechanical properties.

The cost of capturing carbon dioxide (CO2) from ambient air needs to be greatly reduced if it is to contribute significantly to mitigating climate change. Ion-exchange resin (IER) with quaternary ammonium cation binds CO2 when dry and releases it when wet without supplemental energy, making the process attractive for economical Direct Air Capture (DAC). In this study, a design case basis was developed for a system of collectors capable of capturing 1000 tons/day of CO2 via moisture swing sorption. The model uses varying weather parameters such as temperature, wind speed, and relative humidity to understand the impact of weather on the sorbent loading, cycle time (capture and regeneration), and net water loss. Two independent isotherm models, namely Flory Huggins and the modified Langmuir isotherm model were used to estimate the water and CO2 loading of the resin respectively as a function of relative humidity. The capture model suggests a higher capture rate during the summer and daytime (in a diurnal cycle) as the relative humidity is lower. A design optimization model was developed to minimize the capture time and maximize the sorbent loading. The crude rate production and the net water loss can help conduct an economic analysis to determine the cost of carbon capture.

Various research papers and literature were reviewed and consulted for the depolymerization of polyethylene terephthalate (PET) using long chain alkyl amines and ethylene glycol (EG) as catalyst in the aminolysis process. The main hypothesis of this thesis is to use EG as a catalyst in the aminolysis of PET using octylamine, dodecylamine and hexadecylamine. Initial reactions with the three amines were performed with and without EG to observe and compare the terephthalamides obtained from these reactions to test this hypothesis. Various reaction conditions like concentration of reactants, temperature and time of reaction were later considered and employed to find the optimal conditions for the depolymerization of PET before confirming the catalytic properties of EG in the aminolysis reaction. The depolymerized products were subjected to attenuated total reflectance-infrared spectroscopy (ATR-IR Spectroscopy) to check for presence of important amide and ester peaks through their infrared absorption peaks, thermogravimetric analysis (TGA) to find their Td5 temperatures and differential scanning calorimetry (DSC) to check for endothermic melting temperature of the obtained products. These characterization techniques were used to understand, examine, and compare the different properties of the products obtained from different reaction mixtures. The three distinct amines considered for this reaction also showed differences in the conversion rate of PET under similar reaction conditions thus signifying the importance of selecting an appropriate amine reactant for the aminolysis process. Finally, the in-situ IR probe was used to determine the reaction kinetics of the aminolysis reaction and the formation and loss of products and reactants with time.

There are limited analyses of the properties of segmented ionenes on the influence of the type, structure, content of soft/hard segments, and type of counterions through direct comparisons, which are needed for a diverse set of applications. This dissertation research focuses on resolving the gaps in the structure-property-function relationship of segmented ionenes. First, the synthesis of novel segmented ionenes using step-growth polymerization via the Menshutkin reaction of ditertiary amines and alkyl dihalides was performed with PEG soft segment with three different content of soft/hard segments, 25, 50, and 75 wt%, and two different hard segments, linear aliphatic and heterocyclic aliphatic hard segments. The content of the soft segment influenced the degree of phase separation and ionic aggregation which affected the thermomechanical properties of segmented ionenes. In addition, the crystallization of the soft segment influenced the mechanical properties of the ionenes. Second, the effect of the type of the soft segment was investigated by analyzing the novel PTMO-based segmented ionenes possessing three different content of soft/hard segments, as well as two different hard segments. The heterocyclic aliphatic hard segment provided a better degree of phase separation compared to the linear aliphatic hard segment irrespective of the type of soft segment, PEG, or PTMO. Moreover, the type and content of hard segments not only affected the thermal and mechanical properties but also the morphology of the segmented ionenes significantly that even inducing an ordered morphology. Third, the counter-anion metathesis was performed with PEG- and PTMO-based segmented ionenes possessing two structurally different hard segments to investigate the effect of the type of counter-anions with a direct comparison of the type of soft and hard segments. The type of counterion significantly influenced the thermomechanical properties of the segmented ionenes, and the degree of phase separation of different types of counter-anions was dependent on the type of soft and hard segments. The results of this dissertation provide fundamental insights into the correlations between each factor that influences the properties of the segmented ionenes and enable the design of segmented ionenes for a diverse range of applications.