The agricultural industry has an opportunity to shift to a more sustainable practice that helps restore vital topsoil, improve water quality, reduce environmental impact, and sequester atmospheric carbon into the vast soil carbon pool. However, to implement these practices at considerable scale, agricultural producers require access to resources and capital they rarely have and can be difficult to acquire. As a company, investing in regenerative agriculture in supply chains can lead to reduced Scope 3 emissions, more resilient supply chains, and better marketability as an investment fund, an employer, and a brand. Insetting regenerative agriculture can protect supply chains against climate risks and productivity loss, as well as serve as a more secure alternative to carbon credit offsets. Four successful companies, General Mills, Organic Valley, Nestlé, and Nespresso, have been shown to benefit from investing in regenerative agriculture as part of their evolution towards reaching net zero emissions. Based on their strategies, this paper has developed a recommended framework for programming investments for insetting regenerative agriculture. The recommendations rest on six pillars: 1) determining impact, 2) providing direct support to farmers, 3) place-specific strategies, 4) collaboration through partnerships, 5) scalable programming, and 6) educate consumers. Together, these represent a comprehensive approach to insetting that will provide long-term benefits to businesses, suppliers, and the planet.

The Atlantic Meridional Overturning Circulation (AMOC) is thought to exert considerable influence over the climate via heat redistribution and carbon storage. Its repeated variations along with the regional and global climate during the last glacial cycle suggest that the state of the AMOC may be roughly divided into “warm,” “cold,” and “off” modes. The three modes correspond to the vigorous deepwater formation in the subpolar North Atlantic, a reduced deepwater formation, and the widespread disruption of the AMOC, respectively. Questions remain about the cause and response of AMOC perturbations in each of the three modes.Reconstruction of the burial flux of ice-rafted debris can resolve questions about the timing and rates of ice sheet calving, which may have been responsible for the “off” mode of the AMOC, given the association of freshwater forcing with AMOC strength. The first chapter quantified the flux of ice-rafted debris in a pair of cores collected from sites in the western North Atlantic. The results show higher ice-rafted debris flux during all Heinrich events and that the western North Atlantic fluxes were higher than the east. The data demonstrate that the Laurentide Ice Sheet played a role in all Heinrich events. A catastrophic last interglacial Laurentide outburst (LILO) event some 125,000 years ago (125 ka) may have contributed to abrupt climate change during the Eemian, when the AMOC was in the “warm” mode. The LILO event was previously proposed to be an analog of the Holocene 8.2 ka event. The second chapter investigated the age and chemical compositions of a layer of red sediments deposited across much of the Northwest Atlantic at 125 ka. The results provide strong support for the occurrence of the LILO event that was analogous to the 8.2 ka event in provenance, timing, and delivery. Little is known about the zonal (east/west) characteristics of the AMOC when in the “cold” mode during the Last Glacial Maximum. Authigenic uranium preserved in sediments is a sensitive redox tracer and can shed light on bottom water oxygen, carbon storage, and water mass distributions. In the third chapter, new and published authigenic uranium data were used to reconstruct deep ocean oxygenation. The compilation shows that lower-than-Holocene oxygen and correspondingly greater respired carbon storage were persistent features of the LGM in the deep North Atlantic. The eastern basin was substantially less well oxygenated than the west. A farther advance and greater infilling in the east of deep waters originating from the Southern Ocean may have caused the zonal difference. Alternatively, deep waters originating from the subpolar North Atlantic may have increased in their residence time in the eastern transect. Questions remain about the flux of freshwater necessary to induce the AMOC to enter the “off” mode. Existing estimates do not agree on the freshwater fluxes associated with Heinrich events. The fourth chapter uses compiled 230Thxs-based mass fluxes in the North Atlantic during the last glacial period to calculate the surge mass fluxes as a measure of the rate of ice-rafted debris deposition. The surge mass fluxes were then converted into freshwater fluxes. Freshwater fluxes for an arbitrarily defined 2000-year period and total freshwater volumes between 20° and 70° N were as high as 0.11 Sv and 6.9 × 1015 m³ during Heinrich event 4 and as low as 0.0012 Sv and 7.6 × 1013 m³ during Heinrich event 3. The relatively low freshwater fluxes we reconstructed for Heinrich events might suggest potentially a high sensitivity of the Atlantic Meridional Overturning Circulation to freshwater perturbations, although the freshwater volumes are in line with previous reconstructions. Our project represents the first time an attempt made to reconstruct the freshwater fluxes and volumes during all Heinrich events of the last glacial period.

Skanska, Sweden’s leading project development and construction groups, is increasingly striving for innovative solutions to reduce the carbon footprint of its operations and close the loop on waste materials. The company has expressed interest in investing in a pyrolysis plant in the Stockholm region to produce biochar out of wood waste from construction sites. Biochar, a charcoal-like substance, is produced through thermochemical decomposition of biomass. Recently recognized as a negative emissions technology thanks to its ability to act as a carbon sink, and with its many properties and applications, biochar has in recent years become an increasingly valued product on the Nordic market. However, the magnitude with which biochar production mitigates climate change depends on a number of parameters. The present thesis seeks to assess the potential of biochar production at Skanska and use for urban soils to reduce the company’s GHG emissions, and puts results in perspective with Skanska’s sustainability targets. Using the GHG Protocol for Project Accounting, and through a life-cycle perspective, the thesis examines whether biochar production results in a higher climate gain compared to the continuation of current activities, i.e. the treatment of wood waste through incineration for energy recovery. The results show that reductions in emissions depend on a number of factors including biochar stability, biochar yield, the availability of excess heat from the pyrolysis process and its use for district heating, and most importantly, the type of fuel substituted by waste wood for energy production. Ultimately, the quality, quantity, and geographic distribution of wood waste produced by Skanska determines the viability of this project, and this information should be carefully compiled by the company. / Skanska AB, Sveriges ledande bygg- och projektutvecklingsföretag, strävar alltmer efter innovativa lösningar för att minska koldioxidavtrycket i sin verksamhet och sluta cirkeln för avfallsmaterial. Företaget har uttryckt ett intresse att investera i en pyrolysanläggning i Stockholmsregionen för att producera biokol av träavfall från byggarbetsplatser. Biokol produceras genom termokemisk sönderdelning av biomassa och blev nyligen erkänd som en negativ utsläppsteknologi tack vare sin förmåga att fungera som kolsänka. Med sina många användningsområden och varierande egenskaper har biokol under senare år blivit en allt högre värderad produkt på den nordiska marknaden. Dock spelar flera faktorer roll när möjligheterna för biokolsproduktion att reducera klimatförändringarna ska bedömas. Det här examensarbetet syftar till att utvärdera potentialen för biokolsproduktion inom Skanska och användandet av biokol i urbana jordar för att minska företagets växthusgasutsläpp, samt sätta resultaten i perspektiv med Skanskas hållbarhetsmål. Genom att använda GHG-protokollet för projektredovisning, samt ur ett livscykelperspektiv, undersöker examensarbetet huruvida biokolproduktionen resulterar i en högre klimatnytta jämfört med den nuvarande verksamheten, det vill säga genom förbränning av träavfall för energiåtervinning. Resultaten visar att utsläppsminskningar beror på ett antal faktorer, inklusive biokolets stabilitet, produktionsutbyte, tillgång till överskottsvärme från pyrolysprocessen för användning i fjärrvärmenätet, samt viktigast av allt, vilken typ av bränsle som ersätts av träavfall för energiproduktion. I slutändan är det kvaliteten, kvantiteten samt geografisk tillgång till producerat träavfall för biokolsproduktion som avgör hur väl detta projekt kan genomföras, och denna information bör noggrant sammanställas av Skanska.

Geological carbon dioxide (CO2) sequestration (GCS) in deep saline aquifers is viewed as a viable solution to dealing with the impact of anthropogenic CO2 emissions on global warming. The trapping mechanisms that control GCS include capillary trapping, structural trapping, dissolution trapping, and mineral trapping. Wettability and density-driven convection play an important role in GCS, because wettability significantly affects the efficiency of capillary trapping, and density-driven convection greatly decreases the time scale of dissolution trapping. This work focuses on the role of wettability on multiphase flow in porous media, density-driven convection in porous media, and their implications for GCS in deep saline aquifers. Wettability is a critical control over multiphase fluid flow in porous media. However, our understanding on the wettability heterogeneity of a natural rock and its effect on multiphase fluid flow in a natural rock is limited. This work innovatively models the heterogeneous wettability of a rock as a correlated random field. The realistic wetting condition of a natural rock can be reconstructed with in-situ measurements of wettability on the internal surfaces of the rock. A Bentheimer sandstone was used to demonstrate the workflow to model and reconstruct a wettability field. Relative permeability, capillary pressure-water saturation relation are important continuum-scale properties controlling multiphase flow in porous media. This work employed lattice Boltzmann method to simulate the displacement process. We found that pore-scale surface wettability heterogeneity caused noticeable local scCO2 and water redistributions under less water-wet conditions at the pore scale. At the continuum scale, the capillary pressure-water saturation curve under the heterogeneous wetting condition was overall similar to that under the homogeneous wetting condition. This suggested that the impact of local wettability heterogeneity on the capillary pressure-water saturation curve was averaged out at the entire-sample scale. The only difference was that heterogeneous wettability led to a negative entry pressure at the primary drainage stage under the intermediate-wet condition. The impact of pore-scale wettability heterogeneity was more noticeable on the relative permeability curves. Particularly, the variation of the scCO2 relative permeability curve in the heterogeneous wettability scenario was more significant than that in the homogenous wettability scenario. Results showed that higher wettability heterogeneity (i.e., higher standard deviation and higher correlation length) increased the variations in the CO2/brine relative permeability curves. Dissolution of CO2 into brine is a primary mechanism to ensure the long-term security of GCS. CO2 dissolved in brine increases the CO2-brine solution density and thus can cause downward convection. Onset of density-driven instability and onset of convective dissolution are two critical events in the transition process from a diffusion-dominated regime to a convection-dominated regime. In the laboratory, we developed an empirical correlation between light intensity and in-situ solute concentration. Based on the novel and well-controlled experimental methods, we measured the critical Rayleigh-Darcy number and critical times for the onset of density-driven instability and convective dissolution. To further investigate the impact of permeability heterogeneity on density-driven convection, a three-dimensional (3D) fluidics method was proposed to advance the investigation on density-driven convection in porous media. Heterogeneous porous media with desired spatial correlations were efficiently built with 3D-printed elementary porous blocks. In the experiments, methanol-ethylene-glycol (MEG), was used as surrogate fluid to CO2. The heterogeneous porous media were placed in a transparent tank allowing visual observations. Results showed that permeability structure controlled the migration of MEG-rich water. Permeability heterogeneity caused noticeable uncertainty in dissolution rates and uncertainty in dissolution rates increases with correlation length. To sum up, this work comprehensively employed novel experimental methods and large-scale direct simulations to investigate the sequestration of CO2 in saline aquifers at a pore scale and a continuum scale. The findings advanced our understanding on the role of wettability heterogeneity and permeability heterogeneity on GCS in deep saline aquifers. / Doctor of Philosophy / Global warming caused by anthropogenic CO2 emissions is a pressing issue to address of our time. The storage of CO2 in deep saline aquifers is a promising solution because of saline aquifers' vast storage capacity. Property heterogeneity exists extensively in saline aquifers from a continuum scale to a pore scale. The implications of pore-scale wettability heterogeneity and continuum-scale permeability heterogeneity for the storage of CO2 in saline aquifers are not clear. This work is to employ novel experimental methods and powerful simulation tools to investigate the role of wettability heterogeneity and permeability heterogeneity on the storage of CO2 in saline aquifers. This work measured contact angles on the scanned micro-CT images of a Bentheimer sandstone after a CO2 flooding. A correlated lognormal wettability model was put forward with the statistical information of the contact angle measurements. Simulations on the CO2/brine flow in the Bentheimer sandstone were performed. Results showed that the wettability heterogeneity caused noticeable redistributions of CO2/brine compared to scenarios under homogeneous wettability. Impact of wettability on capillary pressure-water saturation curve was not noticeable because the effects were averaged out through the entire rock sample. The standard deviation and correlation length caused variations on the relative permeabilities. This means that we need to take them into consideration in simulating the migration of CO2 in saline aquifers at a reservoir scale. After CO2 pools beneath the impermeable cap rock, dissolution of CO2 into brine dominates the trapping process. Convection caused by CO2 dissolution can greatly accelerate the dissolution rate. The onset of convection is a critical issue and lack of experimental evidence. This work firstly determined the onset time of instability. To further investigate the heterogeneity on the convection, this work proposed a 3D-print-based method to efficiently build heterogeneous porous media with a designed permeability distribution. The experiments were conducted, and results showed that heterogeneity structure of porous media can cause great variations on the dissolution rate of CO2. The findings of this work advanced our understanding on the migration of CO2 in saline aquifers, provided solid basis for assessment and decision on the storage of CO2 into saline aquifers.

Deep row incorporation (DRI) is a biosolids recycling method that is especially appropriate for reclaiming disturbed land because of the extremely high application rates used. Nutrient additions in excess of the vegetation requirements, especially in coarse-textured soils, can potentially impair water quality. Increasing C and N additions with biosolids DRI can also generate emissions of greenhouse gases N₂O and CH₄ and decrease the value of C sequestration. Objectives of this research were: (i) compare the effects of DRI biosolids type and rate and annual conventional fertilizer application on N and P leaching losses; (ii) determine the effects of aging on the N, C and P dynamics in the DRI biosolids seams; (iii) compare the effects of biosolids type and conventional N fertilization on N₂O, CH₄ and CO₂ emissions; and (iv) compare the effects of DRI biosolids and conventional N fertilization on hybrid poplar biomass dynamics, C, N and P sequestration. The following eight treatments were established to achieve objectives (i) and (iv): 0 (control), 167, 337, 504 kg N ha⁻¹ yr⁻¹ as conventional fertilizer; 213 and 426 Mg ha⁻¹ anaerobically digested (AD) and 328 and 656 Mg ha⁻¹ lime stabilized (LS) biosolids applied in trenches. The amount of N lost from the DRI biosolids was 261–803 kg N ha⁻¹, while the fertilizer treatments were not different from 0 kg N ha⁻¹ yr⁻¹ control. Orthophosphate and TKP leached in negligible amounts. Deep row biosolids incorporation did not pose P leaching risks but did result in high N leaching below the biosolids seams. Aboveground biomass production in the biosolids treatments was not different from the control treatment and ranged from 2.1±0.3 to 4.0±0.5 kg tree⁻¹. The fertilizer treatments produced significantly less biomass than the control and the biosolids treatments. Hybrid poplars sequestered up to 3.20±0.54 Mg C ha⁻¹, 71±12 kg N ha⁻¹, and 11.0±1.8 kg P ha⁻¹. The planting density capable of the N uptake in order to avoid N leaching was estimated at 3912 to 11363 trees ha⁻¹. Our results suggest increased hybrid poplar planting density and decreased application rates of DRI biosolids may decrease the risk of groundwater contamination with N. Three treatments were compared to address objective (ii): 426 Mg ha⁻¹ AD and 656 Mg ha⁻¹ LS biosolids. Organic C losses were 81 Mg ha⁻¹ and 33 Mg ha⁻¹ for LS and AD biosolids, respectively. Total N lost over the course of two years was 15.2 Mg ha⁻¹ and 10.9 Mg ha⁻¹ for LS and AD biosolids, respectively, which was roughly 50% of the N applied. No significant losses of P were detected. Most of the P was Al- and Fe-bound in the AD biosolids and Ca-bound in the LS biosolids. Our results indicated that recommended rates of DRI biosolids in coarse textured soils should be based on crop N requirements and N mineralization considerations, and P mobility from biosolids of the type used should not pose a water quality risk. Four treatments were compared to address objective (iii): 426 Mg ha⁻¹ AD and 656 Mg ha⁻¹ LS biosolids; 0 (control) and 504 kg N ha⁻¹ y⁻¹ as conventional fertilizer. Contributions from CH₄ and CO₂ emissions to the radiative forcing were very small compared to N₂O. More N₂O was produced in the DRI biosolids treatments than in the conventional fertilizer treatments, and N₂O production was higher in AD than in LS. Expressed as global warming potentials, N₂O emissions from AD (101.5 Mg C ha⁻¹) were 4.6 times higher than from LS and 14.5-16.1 times higher than from the fertilizer treatments. High N₂O emissions from deep row incorporated biosolids reduce the C sequestration benefits of the DRI method. / Ph. D.

The thinning of loblolly pine plantations has a great potential to influence the fluxes and storage of carbon within managed stands. This study looked at the effects of thinning on aboveground carbon and mineral soil carbon storage, 14-years after the thinning of an 8-year-old loblolly pine plantation on the piedmont of Virginia. The study also examined soil respiration for one year following the second thinning of the same stand at age twenty-two. The study was conducted using three replicate .222 hectare stands planted using 3.05 by 3.05 meter spacing in 1980 at the Reynolds Homestead in Critz, VA. Using two different sample collection methods it was determined that soil carbon was evenly dispersed throughout thinned plots, and that random sampling techniques were adequate for capturing spatial variability. Soil carbon showed a significant negative correlation with soil depth (p=0.0001), and by testing the difference between intercepts in this relationship, it was determined that thinning significantly increased soil carbon by 31.9% across all depths (p=0.0004). However, after accounting for losses in aboveground wood production, thinning resulted in an overall 10% loss in stand carbon storage. However, this analysis did not take into account the fate of wood products following removal. Soil respiration, soil temperature, and soil moisture were measured every month for one year near randomly selected stumps and trees. In order to account for spatial variation, split plots were measured at positions adjacent to stumps and 1.5 meters away from stumps. Soil temperature and moisture were both significantly affected by thinning. Regression analysis was performed to determine significant drivers in soil CO2 efflux. Temperature proved to be the most significant driver of soil respiration, with a positive correlation in thinned and unthinned stands. When modeled using regression, thinning was a significant variable for predicting soil respiration (p < 0.0009), but explained only 3.4% of the variation. The effects of thinning were responsible for decreased respiration, however, when coupled with increased temperatures, soil respiration was elevated in thinned stands. / Master of Science

Site preparation is fundamental for establishing loblolly pine (Pinus taeda L.) plantations, but long-term sustainability of plantations established using mechanical treatments is in question because of concerns regarding soil tillage and the removal of harvest residue and soil organic matter. A study was installed in 1981 on 12 locations in northeastern Georgia and west-central South Carolina to evaluate pine plantation response to mechanical site preparation. Site preparation treatments induced gradients of organic matter manipulation and soil tillage. The treatments included: Control, Chop/Burn, Shear/Disc, Shear/V-Blade, Shear/Rake, and Shear/Rake/Pile. Research was conducted to address the following objectives: (i) compare rotation-age forest response to several intensive site preparation treatments used to establish pine plantations in the Piedmont of the southeastern United States; (ii) correlate growth response with the gradients of soil organic matter removal, soil tillage, and hardwood control; (iii) determine the influence of intensive management on the amount of carbon contained in pine plantations. All site preparation treatments increased year-18 volume accumulation compared to the control treatment. Chop/Burn and Shear/Disc treatments, with pine volumes of 214 m3 ha-1 and 232 m3 ha-1, respectively, conserved harvest residue and out-performed the Shear/Rake treatment (191 m3 ha-1), which completely removed harvest residue. Treatments that included tillage provided growth benefits that lasted throughout the rotation even when tillage was accompanied by complete organic matter removal. Hardwood competition had the greatest influence on pine volume accumulation, explaining over 54% of the variation in pine growth at age 18. Treatments that included tillage most effectively controlled hardwood competition. At year 18, site preparation treatments significantly affected soil organic matter (SOM) content; however, soil nitrogen, foliar nitrogen, bulk density, and macroporosity were not affected by site preparation. All treatments were equally deficient in foliar nitrogen. The Shear/Disc and Shear/Rake/Disc treatments had a significantly positive relationship between foliar nitrogen and pine volume. These treatments had lower hardwood basal areas (below 15%), indicating that once hardwoods were controlled, nitrogen became limiting to pine growth. Using pre-harvest characterization data, carbon accumulation during old-field succession increased fourfold compared to agricultural sites on the nearby Calhoun Experimental Forest. Carbon accumulation on these old-field loblolly pine sites reached quasi-equilibrium after 40 years as shown by uncut reference stands. Site preparation significantly affected the amount of soil C in the upper 20 cm of the soil. Those site preparation treatments that removed harvest residue and accelerated SOM decomposition through tillage had the lowest soil carbon levels. The Shear/Rake/Disc treatment had 10% lower soil carbon content than the Control and Shear/V-Blade treatments. / Master of Science

An understanding of ecosystem-level carbon (C) sequestration, or net ecosystem production (NEP), requires the separation of heterotrophic, microbial respiration (RH) from autotrophic, root-derived respiration (RA) as the components of RS (i.e., NEP = NPP - RH). However, separating these two sources in situ has been problematic since they are closely coupled. This study utilizes two similarly aged Pinus taeda L. stands, 8 and 9 years-old, aimed at quantifying these two respiration components through in-situ root severing. In order to use root-severing treatments to separate RS into RH and RA components, confirmation of carbohydrate depletion coupled to RA decline is crucial. This study evaluated the changes in CO2 flux rates and carbohydrate supply upon root severing in Pinus taeda L. using a controlled laboratory validating a two-part field study. The first field study used root-severing cores to test in-situ if respiration components can be attained based on the depletion of carbohydrate supply. The second field study was aimed at how future changes in climate might affect the ability of forests to store C and how modern forestry practices might affect changes and was conducted over the course of two installations, spring and summer 2012. In this study we examined the effects of fertilization (0 and 100.9 kg N ha-1 ) and throughfall reduction (0 and -30%) on total soil respiration (RS) as well as the heterotrophic contribution to RS, in a fully replicated (n=4), 2x2 factorial design. In the controlled lab experiment RS and RA declined by 86% and 95% respectively by the end of an 86 day trial and NSC carbohydrates declined by 60% for soluble, 29% for insoluble, and 43% for total (soluble + insoluble). The decline of RA was highly correlated to with the decline of NSC’s at 0.90, 0.69 and 0.93 for soluble, insoluble and total, respectively. The companion field study revealed a mean decrease 21±0.5% of over the final three dates when severed root respiration stabilized. In the second study, testing throughfall reduction and fertilization levels there were no fertilization by throughfall reduction interactions on the contribution of RH to RS in either the spring or summer; however, the main effect of throughfall reduction was significant in the spring. During the spring, the mean contribution of RH to RS for ambient throughfall plots was 96±6.4%, while the mean contribution under throughfall reduction was 68±1.9%. During the summer, there were no differences among treatments and the overall contribution of RH to RS was 78±1.6%. Collectively, both of these studies revealed that the severing of roots from their primary energy source and the subsequent depletion of stored NSC that the use of in-situ methods allows for the quantification of soil respiration components RA and RH. Using these estimates to model NEP in the short-term can be variable by season, however, long-term monitoring may simplify future NEP modeling scenarios / Master of Science

This dissertation explores the development and optimization of Metal-Organic Frameworks (MOFs) and Nanoparticle Organic Hybrid Materials (NOHMs) for efficient CO₂ capture and investigates enhanced sorbent regeneration using a non-thermal transfer. Chapter 2 introduces the versatility and challenges of MOFs, including their structural adaptability and issues with hydrostability, highlighting the need for water-resistant modifications or coatings to maintain functionality in humid conditions. Chapter 3 and 4 focus on advancements in MOF design for CO₂ capture and the synthesis of encapsulated MOFs with enhanced durability against moisture, using HKUST-1 integrated with hydrophobic polymer PTMSP as an example to demonstrate its potential despite challenges in optimizing CO₂ sorption efficiency when exposed to water. Chapter 5 explores NOHMs, particularly ionically tethered polyethylenimine (NIPEI), for creating air-filter-like fiber mat systems with significant CO sorption capabilities, even under low CO₂ concentrations and humid conditions, suggesting further material and design optimization for industrial applications. Chapter 6 presents a modeling study on gas transport behaviors within NOHM-polymer interfaces, utilizing Molecular Dynamics (MD) simulations to enhance our understanding of CO₂ sorption dynamics, pointing towards the importance of ion diffusion rates and the distribution of gas molecules for improved capture efficiency. Chapter 7 delves into CO₂ desorption techniques, comparing microwave radiation to conventional thermal heating, showing the efficiency and energy-saving benefits of microwave regeneration, especially when incorporating Fe₃O₄ magnetite into NOHMs. This chapter also stresses the necessity of innovative reactor designs to ensure uniform heating and address technical challenges like nanoscale temperature measurement and uneven heat distribution. Chapter 8 extends the discussion to future research directions, emphasizing the potential of NOHMs for CO₂ capture and conversion, the exploration of their electrochemical performance, and the need for understanding CO₂ transport mechanisms for enhanced conversion efficiency. It calls for comprehensive evaluations of sorbents in terms of stability, kinetics, capacity, selectivity, and cost-effectiveness, alongside advancements in microwave regeneration technology to overcome current limitations in sorbent heating efficiency. Overall, this dissertation underscores the ongoing need for innovative solutions to improve CO₂ capture technologies, highlighting the promise of MOFs and NOHMs in addressing climate change challenges through scalable carbon capture, utilization, and storage (CCUS) applications.

Since the Industrial Revolution, human society has rapidly developed and flourished. Meanwhile, some interconnected side effects, particularly in realms of water, energy, food and environment, are tackling the sustainability of society. These grand challenges are intricately interconnected, underscoring the importance of addressing these problems through the lens of the water-energy-environment (WEE) nexus, which emphasizes the interlinkages between these sectors. For instance, the unprecedented scale of CO₂ has accumulated in the atmosphere, and it has accelerated global warming and the chained environmental problems, such as droughts and floods. This insecurity for water resources has encouraged water recycling. At the same time, a new class of anthropogenic contaminants, including pharmaceutical and personal care products (PPCP), heavy metals, herbicides or pesticides, and per-fluoroalkyl substances (PFAS), have been accumulated in natural water bodies. These contaminants are called emerging contaminants, and these can potentially cause severe problems in ecology and human health. Thus, this thesis aimed to tackle these multifaceted issues by investigating the interfacial chemistries between the natural or engineered solids and aqueous phases, particularly in the context of in-situ carbon mineralization and water remediation.To mitigate climate change, we should not only reduce CO₂ emissions but also remove the previously emitted CO₂ from the air. In-situ carbon mineralization is a critical technology to meet the agenda of carbon dioxide removal from the air (CDR) as the potential capacity and offer a thermodynamically downhill reaction to store CO₂ permanently in solid form. During the in-situ carbon mineralization, water plays a pivotal role in the interactions at Rock-H₂O-CO₂ interfaces. However, the kinetics and mechanisms of interfacial reactions in the mineral-aqueous phases with various compositions still need to be fully understood. Additionally, in-situ carbon mineralization demands substantial water usage; therefore, addressing water security become imperative. However, during the water usage and recycling process, the accumulation of ions, including heavy metals, and the spreading of organic pollutants can intensify the concerns about water security. Thus, this thesis’s objectives are to focus on a fundamental understanding of reaction kinetics and mechanisms occurring at the interested interfaces to address these challenges. At the mineral-aqueous phase for in-situ carbon mineralization, the effect of parameters, such as temperature, pH, and mineralogy has been assessed for mineral dissolution in the aqueous phase, and both basalt and peridotite were investigated. Related to the dissolution kinetics, this thesis discussed the frameworks for determining the dissolution rate, which can affect our understanding of experimental results. The dissolution studies exploring the effect of various parameters related to the in-situ carbon mineralization provided valuable insights into the reactivity of feedstock and morphological alterations that can be utilized for reactive-transportation modeling. Also, the experiment results may suggest the system boundary to engineer the geological CO₂ storage process. Also, carbonation behaviors were studied in terms of direct carbonation and nucleation. For the direct carbonation, olivine mineral and peridotite rock retrieved from a potential CO₂ storage site were tested, and the effects of parameters including pH, additives, and temperature were discussed. During the in-situ carbon mineralization, dissolved cations and dissolved CO₂ can be nucleated and precipitated on the different types of mineral surfaces. Therefore, this study investigated the interfacial interactions with different types of mineral surfaces and containing ions in the aqueous phase. These studies provide the fundamental understanding of the thermodynamics and kinetics of carbonation during in-situ carbon mineralization. Lastly, this study explored the kinetics and mechanisms of adsorption at adsorbent–emerging contaminant containing fluid interfaces in regard to water remediation and recycling. In this study, biochar from waste streams and MOFs with different modifications were used for the strategical development of adsorbents, while spectroscopic analysis methods were adopted to elucidate the mechanisms. Also, the effect of coexisting ions or reusability was discussed. Further, the results and insights from this investigation can be utilized for developing future generations of adsorbents and designing the remediation process. Consequently, through understanding the various regimes of interfaces, this study may contribute to the advancement of strategic approaches for addressing the complex challenges within the WEE nexus, particularly related to sustainable in-situ carbon mineralization.