Technical methods of carbon capture by seawater-based solution mineral carbonation

Stochastic modeling of decarbonizing strategy, policy, and market-induced incentives for the US electricity sector

Investigating carbonate formation in urban soils as a method for capture and storage of atmospheric carbon

Sustainable exploitation of mafic rock quarry waste for carbon sequestration following ball milling

One of the most promising strategies for the safe and permanent disposal of anthropogenic CO2 is its conversion into carbonate minerals via the carbonation of calcium and magnesium silicates. However, the mechanism of such a reaction is not well constrained, and its slow kinetics is a handicap for the implementation of silicate mineral carbonation as an effective method for CO2 capture and storage (CCS). Here, we studied the different steps of wollastonite (CaSiO3) carbonation (silicate dissolution → carbonate precipitation) as a model CCS system for the screening of natural and biomimetic catalysts for this reaction. Tested catalysts included carbonic anhydrase (CA), a natural enzyme that catalyzes the reversible hydration of CO2(aq), and biomimetic metal-organic frameworks (MOFs). Our results show that dissolution is the rate-limiting step for wollastonite carbonation. The overall reaction progresses anisotropically along different [hkl] directions via a pseudomorphic interface-coupled dissolution–precipitation mechanism, leading to partial passivation via secondary surface precipitation of amorphous silica and calcite, which in both cases is anisotropic (i.e., (hkl)-specific). CA accelerates the final carbonate precipitation step but hinders the overall carbonation of wollastonite. Remarkably, one of the tested Zr-based MOFs accelerates the dissolution of the silicate. The use of MOFs for enhanced silicate dissolution alone or in combination with other natural or biomimetic catalysts for accelerated carbonation could represent a potentially effective strategy for enhanced mineral CCS.

Carbon Capture and Storage (CCS) is a vital climate mitigation strategy aimed at reducing CO2 emissions from industrial and energy sectors. This review presents a comprehensive analysis of CCS technologies, focusing on capture methods, transport systems, geological storage, geomechanical and geochemical aspects, modeling, risk assessment, monitoring, and economic feasibility. Among capture technologies, pre-combustion capture is identified as the most efficient (90–95%) due to its high purity and integration potential. Notably, most operational CCS projects in 2025 utilize pre-combustion capture, particularly in hydrogen production and natural gas processing. For geological storage, saline aquifers and depleted oil and gas reservoirs are highlighted as the most promising due to their vast capacity and proven containment. In the transport phase, pipeline systems are considered the most effective and scalable method, offering high efficiency and cost-effectiveness for large-scale CO2 movement, especially in the supercritical phase. The study also emphasizes the importance of hybrid integrated risk assessment models, such as NRAP-Open-IAM, which combine deterministic simulations with probabilistic frameworks for robust site evaluation. In terms of monitoring, Seismic monitoring methods are regarded as the most reliable subsurface technique for tracking CO2 plume migration and ensuring storage integrity. Economically, depleted reservoirs offer the most feasible option when integrated with existing infrastructure and supported by incentives like 45Q tax credits. The review concludes that successful CCS deployment requires interdisciplinary innovation, standardized risk protocols, and strong policy support. This work serves as a strategic reference for researchers, policymakers, and industry professionals aiming to scale CCS technologies for global decarbonization.

One of the emerging areas in combatting environmental issue like global warming is carbon capture and storage (CCS) entices a solution by not limiting output of any operation. Carbon capture storage refers to the process of capturing or gathering carbon dioxide released into the atmosphere from various activities and injecting the captured gas underground (aquifer). CCS can be divided into 3 main stages namely capturing, transportation and storage. The carbon dioxide will be captured from a source, being transported and sequestrated underground. In this paper, the main area discussed is the capturing process and application in steelmaking industry from economical point of view. Carbon capture is an expensive process which creates an indecisiveness among different parties to actually put the process in practice. However, this expensive process is not properly quantified which is the main motivation of this study to contribute to the cost quantification of carbon capture. Carbon capture is mainly divided to several methods namely membrane separation, oxyfuel combustion, absorption, adsorption, chemical looping combustion, calcium looping and cryogenic method. Despite of having many capturing methods available, there was no vivid or clear application at a large commercial or industrial scale of several methods which rendered them mooted for comparison's sake. Technologies that have gone beyond technological readiness level (TRL) 4 shall be considered since the relevancy of the comparison can benefit parties planning to spearhead or undertake CCS.

Legal requirements are increasingly promoting the thermal treatment of sewage sludge in Germany, and alternative disposal methods are being investigated. Oxyfuel combustion is one promising thermal process for treating sewage sludge. However, the flue gas produced during the combustion process contains high levels of CO2, a greenhouse gas that poses environmental harm. To address this issue, this study analyzed oxyfuel combustion and various CO2 capture methods, aiming to utilize CO2 as a feedstock for methanol production. Energy and material balance simulations were carried out using Aspen Plus. Four distinct carbon capture methods: membrane carbon capture, cryogenic carbon capture, monoethanolamine carbon capture, and ionic liquid carbon capture were modeled. Three different oxygen configurations were tested: pure air, pure oxygen, and a 50/50 air–oxygen mixture. The oxygen separation systems, including air separation units and alkaline electrolyzers, were also studied and modeled. As a result, 14 different scenarios were created. The performances, energy efficiency, and economic results of each scenario were compared to one another and to existing literature, allowing for the identification of the most effective approaches. The oxyfuel combustion scenarios achieved the highest methanol output. MEA and ionic liquid capture combined with air combustion proved to be the most cost-effective options, while cryogenic capture incurred the highest costs due to its helium-based cooling requirements. Although ASU-based oxyfuel combustion achieved the lowest specific energy requirement for methanol production, electrolysis-integrated configurations remained economically disadvantageous, underscoring the critical influence of electricity prices on the overall feasibility of the system.

Toward solvent-free continuous-flow electrochemically mediated carbon capture with high-concentration liquid quinone chemistry

Carbon dioxide (CO2) is a significant contributor to global warming and environmental issues, necessitating the development of practical storage solutions. As an alternative to CO2 storage in subsurface formations, mineral carbonation, which offers long-term CO2 storage and advantages like thermodynamics and energy economy, is gaining popularity. Also, the possible repurposing of carbonated solid waste in the building and construction industry contributes to the reduction of CO2. However, large-scale implementation of natural mineral carbonation remains a challenge. This study investigates the comparative advantages and disadvantages of direct solid-gas and direct aqueous carbonation, two carbon capture and storage (CCS) methods for combating atmospheric CO2 emissions. The research focuses on reaction kinetics, capture efficiency, recovery efficiency, leakage security, and cost-effectiveness. Both methods have the potential to capture CO2 efficiently, but they differ in their effectiveness and feasibility. Direct solid-gas carbonation exhibits higher reaction rates and capture efficiency, while direct aqueous carbonation has lower energy requirements and is easier to implement at ambient temperature and pressure. Further research is essential to fully understand the comparative merits and drawbacks of direct solid-gas and aqueous carbonation and devise strategies to minimize their environmental impact. Furthermore, to ensure economic feasibility, future research should focus on lowering CO2 sequestration costs, increasing the scale of captured CO2 usage in industrial processes, and developing a circular economy by transforming captured CO2 into valuable metal carbonates.

Human activities are now responsible for the annual emission of some 31.6 billion tonnes of dioxide, which contains 8.6 billion tonnes of carbon, causing the total atmospheric burden of C[H.sub.2] to reach 400 ppm, above the Arctic, and 395 ppm globally (1). In order to mitigate the rise in C[H.sub.2] concentration and ideally to reduce it, various methods for capture and storage (2) (CCS) have been proposed, also known as carbon capture and sequestration. To this amount of C[H.sub.2] entirely would require phenomenal levels of engineering since around 87 million tonnes per day of C[H.sub.2] would need to be captured. There are essentially two methods to remove from fuel: post-combustion and precombustion. In post-combustion treatment, the flue-gas of a power station is passed through a liquid amine (e.g. ethanolamine and its derivatives) which dissolves the C[O.sub.2] from it. In the pre-combustion approach, the fuel (coal, gas, biomass) is processed into a mixture of C[O.sub.2] + [H.sub.2] and the C[O.sub.2] is removed: initially, a mixture of CO + [H.sub.2]O is produced [Eqn (1)] but the CO is converted to C[O.sub.2] by reaction with [H.sub.2]O, squeezing-out another molecule of [H.sub.2] in the process [water-gas shift reaction; Eqn (2)]. Following either method, the C[O.sub.2] must be stored somewhere (Figure 1), for which strategies include pumping it into rocky formations (such as depleted oil and gas wells) at a pressure of 100 atmospheres, or even piping it in liquid form under pressure onto the sea-floor where it is cold enough and the pressure high enough that it is hoped the material will stay there, assisted by the formation of C[O.sub.2]-hydrate. These and other aspects of CCS are now elaborated upon. [FIGURE 1 OMITTED] Capture While the extraction of C[O.sub.2] from the air is technically possible, the gas is most readily captured at point sources (2) e.g. large fossil fuel or biomass power plants, industries with major C[O.sub.2] emissions such as cement factories, natural gas processing plants, and hydrogen production plants which generate syngas by steam-reforming [Eqn (1)] and convert the CO to C[O.sub.2] using the water-gas shift reaction [Eqn (2)]: C[H.sub.4] + 2[H.sub.2]0 [right arrow] CO + 3[H.sub.2] (1) CO + [H.sub.2]O [right arrow] C[O.sub.2] + [H.sub.2] (2) As the distance from the point source increases, the concentration of C[O.sub.2] falls rapidly which necessitates an increase in the amount of air that must be processed per unit mass of C[O.sub.2] captured. The combustion of coal in oxygen produces a relatively pure, concentrated stream of C[O.sub.2], which might be processed directly. Organisms that produce ethanol by fermentation generate cool, and practically pure, C[O.sub.2] which is suitable for underground storage. World ethanol production in 2008 was close to 16 billion US gallons, which at a density of 789.00 kg [m.sup.-3] amounts to 61,000,000 [m.sup.3] or 48 million tonnes of the material (3). There are essentially three principal methods for capturing C[O.sub.2]: post-combustion, pre-combustion, and oxyfuel combustion: * In post-combustion capture, the C[O.sub.2] is removed following combustion of the fossil fuel, i.e. the scheme that would be used to reduce emissions from fossil-fuel fired power plants. The technology is well understood and is used in other industrial applications, although some considerable scale-up would be required to deal with the C[O.sub.2] output from a standard (e.g. I GW) power station, which might burn 3.5 million tonnes of coal per year. * Pre-combustion capture might be accomplished using the kind of technology that is used to make (ammonia for) fertiliser, and fuels ([H.sub.2], C[H.sub.4]),and for power production (4).The reactions described in Eqns (1) and (2) prevail, and the final C[O.sub.2] can be extracted from a relatively pure exhaust stream, leaving [H. …

Introduction to Carbon Capture and Storage

Superstructure optimisation in various carbon capture and utilisation supply chains

Industrial pollution is the major source of global warming through emissions of greenhouse gases (GHG’s) like CO2, CH4, and NO2, causing noticeable increasing in the world’s temperature. Mineral carbonation is a method of carbon capture and storage (CCS) through which CO2 is sequestered with advantage of permanent sequestration and no need for post-storage surveillance and monitoring through stabilizing the reactive mineral wastes released from metal industries. This paper applied a simple and an inexpensive hydration process as a pre-treatment step for the carbonation of Ladle Furnace (LF) slag, one of the steel production by-products in UAE, followed by direct gas-solid carbonation in a new designed integrated fluidized bed reactor (FBR). About (10–15)% by weight of produced steel, alkaline solid residues were generated, based on the characteristics of the manufacturing process. The integrated FBR was designed to control the flow rate up to 50 l/min with step accuracy of 0.1 l/min, and temperature up to 200 °C through a double jacket electrical heater. Operating pressure can be adjusted up to 6 bars. All parameters are monitored by SCADA system. A mixture gas of 10% CO2, balanced with air, was used to perform the carbonation process and evaluation the carbonation efficiency as well. A gas analyzer installed at the outlet of FBR was used to measure unreacted CO2 gas after leaving the reactor, and calculate the amount of CO2 captured accordingly. Results of analytical techniques like TGA and XRD emphasized the sequestration of CO2 and show a high efficient carbonation process.

In recent years, human activities have led to significant CO2 emissions. The increase in energy consumption and emissions of greenhouse gases (mainly CO2) has led to consequences such as global warming and an accelerated rate of glacial melting, making global environmental development more challenging. Even though the monoethanolamine (MEA) method of capturing carbon dioxide is now widely used in industry, the disadvantages of this method still exist, mainly because of the difficult economic balance. Since CO2 is inevitable due to human activities, converting the generated CO2 into high-value clean energy to alleviate the greenhouse effect is a current research hotspot. Therefore, finding a perfect method for capturing CO2 from industrial and commercial operations as soon as possible is certainly a high priority. This paper provides an overview of the basic principles and practical applications of physical and chemical methods of CO2 capture and biochemical technology in the conversion of the captured CO2 into value-added products. The paper describes the current status and challenges faced in the application of carbon capture and storage (CCS) technology worldwide, and finally shows the advantages and prospects of each method. This will lead to the development of a new carbon economy with commercial value, which in turn will facilitate the implementation of CCS on a global scale, ultimately leading to the goal of global carbon neutrality.

Evaluation of multiple time carbon capture and storage network with capital-carbon trade-off