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It is significant to investigate the calcium carbonate (CaCO3) precipitation mechanism during the carbon capture process; nevertheless, CaCO3 precipitation is not clearly understood yet. Understanding the carbonation mechanism at the atomic level can contribute to the mineralization capture and utilization of carbon dioxide, as well as the development of new cementitious materials with high-performance. There are many factors, such as temperature and CO2 concentration, that can influence the carbonation reaction. In order to achieve better carbonation efficiency, the reaction conditions of carbonation should be fully verified. Therefore, based on molecular dynamics simulations, this paper investigates the atomic-scale mechanism of carbonation. We investigate the effect of carbonation factors, including temperature and concentration, on the kinetics of carbonation (polymerization rate and activation energy), the early nucleation of calcium carbonate, etc. Then, we analyze the local stresses of atoms to reveal the driving force of early stage carbonate nucleation and the reasons for the evolution of polymerization rate and activation energy. Results show that the higher the calcium concentration or temperature, the higher the polymerization rate of calcium carbonate. In addition, the activation energies of the carbonation reaction increase with the decrease in calcium concentrations. [ABSTRACT FROM AUTHOR]

Agriculture is a major contributor to greenhouse gas emissions and is vulnerable to climate change. Regenerative agriculture, which focuses on increasing soil carbon, has been recognized as a potential climate solution. A recent study found that seven regenerative practices, including planting cover crops and using non-chemical fertilizers, all increased carbon sequestration. However, the study also highlights that regenerative agriculture has other benefits beyond carbon sequestration, and the focus should not solely be on carbon credits. The popularity of regenerative agriculture is growing, but there is a risk of it being co-opted and losing its essence. [Extracted from the article]

Contemporary resource management is doubly burdened by high rates of organic material disposal in landfills, generating potent greenhouse gases (GHG), and globally degraded soils, which threaten future food security. Expansion of composting can provide a resilient alternative, by avoiding landfill GHG emissions, returning valuable nutrients to the soil to ensure continued agricultural production, and sequestering carbon while supporting local communities. Recognizing this opportunity, California has set ambitious organics diversion targets in the Short-Lived Climate Pollutant Law (SB1383) which will require significant increases (5 to 8 million tonnes per year) in organic material processing capacity. This paper develops a spatial optimization model to consider how to handle this flow of additional material while achieving myriad social and ecological benefits through compost production. We consider community-based and on-farm facilities alongside centralized, large-scale infrastructure to explore decentralized and diversified alternative futures of composting infrastructure in the state of California. We find using a diversity of facilities would provide opportunity for cost savings while achieving significant emissions reductions of approximately 3.4 ± 1 MMT CO2e and demonstrate that it is possible to incorporate community protection into compost infrastructure planning while meeting economic and environmental objectives.

Tropical rainforests of Latin America (LATAM) are one of the world's largest carbon sinks, with substantial future carbon sequestration potential and contributing a major proportion of the global supply of forest carbon credits. LATAM is poised to contribute predominantly towards high-quality forest carbon offset projects designed to reduce emissions from deforestation and forest degradation, halt biodiversity loss, and provide equitable conservation benefits to people. Thus, carbon markets, including compliance carbon markets and voluntary carbon markets continue to expand in LATAM. However, the extent of the growth and status of forest carbon markets, pricing initiatives, stakeholders, amongst others, are yet to be explored and extensively reviewed for the entire LATAM region. Against this backdrop, we reviewed a total of 299 articles, including peer-reviewed and non-scientific gray literature sources, from January 2010 to March 2023. Herein, based on the extensive literature review, we present the results and provide perspectives classified into five categories: (i) the status and recent trends of forest carbon markets (ii) the interested parties and their role in the forest carbon markets, (iii) the measurement, reporting and verification (MRV) approaches and role of remote sensing, (iv) the challenges, and (v) the benefits, opportunities, future directions and recommendations to enhance forest carbon markets in LATAM. Despite the substantial challenges, better governance structures for forest carbon markets can increase the number, quality and integrity of projects and support the carbon sequestration capacity of the rainforests of LATAM. Due to the complex and extensive nature of forest carbon projects in LATAM, emerging technologies like remote sensing can enable scale and reduce technical barriers to MRV, if properly benchmarked. The future directions and recommendations provided are intended to improve upon the existing infrastructure and governance mechanisms, and encourage further participation from the public and private sectors in forest carbon markets in LATAM.

Microbial community dynamics on sinking particles control the amount of carbon that reaches the deep ocean and the length of time that carbon is stored, with potentially profound impacts on Earths climate. A mechanistic understanding of the controls on sinking particle distributions has been hindered by limited depth- and time-resolved sampling and methods that cannot distinguish individual particles. Here, we analyze microbial communities on nearly 400 individual sinking particles in conjunction with more conventional composite particle samples to determine how particle colonization and community assembly might control carbon sequestration in the deep ocean. We observed community succession with corresponding changes in microbial metabolic potential on the larger sinking particles transporting a significant fraction of carbon to the deep sea. Microbial community richness decreased as particles aged and sank; however, richness increased with particle size and the attenuation of carbon export. This suggests that the theory of island biogeography applies to sinking marine particles. Changes in POC flux attenuation with time and microbial community composition with depth were reproduced in a mechanistic ecosystem model that reflected a range of POC labilities and microbial growth rates. Our results highlight microbial community dynamics and processes on individual sinking particles, the isolation of which is necessary to improve mechanistic models of ocean carbon uptake.

Argon Power Cycle (APC) combustion engine has a high efficiency, zero carbon emissions, and zero pollutant emissions, rendering it a promising way for achieving zero or carbon neutrality within the realm of internal combustion engine (ICE) technology. Previous studies have shown that while APCs significantly improve the thermal efficiency of ICEs, they also face serious knock problems due to their high temperatures and pressures, especially when hydrogen is used as a fuel. In this study, the anti-knocking characteristics of hydrogen, methane, carbon monoxide, and ammonia were first investigated in APC through thermodynamic calculations by Ignition Delay Time. Then, based on testbench experiments, hydrogen and methane fuels were selected to further investigate the effect of different fuel anti-knocking characteristics on the indicated thermal efficiency and power of APC combustion engine. Test results showed that when using hydrogen, the APC ICE exhibited a pronounced knock tendency, and the test engine could not operate stably when the excess oxygen ratio <2.1 at compression ratio = 9.6. The CA50 of the maximum efficiency point was delayed in APC than in air for both hydrogen and methane, specially H 2 has an obvious lag at about 5–15 ° CA. In comparison, when using methane, the combustion control of engine is easier, and the peak indicated thermal efficiency 59% and the peak indicated mean effective pressure 0.92 MPa are higher than 54.3% and 0.60 MPa of using hydrogen. The use of hydrogen still needs an anti-knocking strategy while an extra carbon capture device is necessary to ensure a closed argon cycle if methane is employed. • Ignition Delay Time calculated by simulation presents a good judgement to evaluate knocking-resistance for gaseous fuel. • Evaluating the knock in the APC ICE employing the CA50 of max efficiency verifies that CH 4 has a better knocking-resistance. • Due to better knock resistance, CH 4 -fueled APC ICE achieved higher thermal efficiency +4.7% and IMEP +0.32MPa than H 2. [ABSTRACT FROM AUTHOR]

Summary Bark serves crucial roles in safeguarding trees physically and chemically, while also contributing to nutrient cycling and carbon sequestration. Despite its importance, the broader biogeographical patterns and the potential factors influencing bark C : N : P stoichiometry in forest ecosystems remain largely unknown. In this study, we compiled a comprehensive dataset comprising carbon (C), nitrogen (N), and phosphorus (P) concentrations in bark with 1240 records from 550 diverse forest sites to systematically analyze the large‐scale patterns and the factors controlling bark C : N : P stoichiometry. The geometric means of bark C, N, and P concentrations were found to be 493.17 ± 1.75, 3.91 ± 0.09, and 0.2 ± 0.01 mg g−1, respectively. Correspondingly, the C : N, C : P, and N : P mass ratios were 135.51 ± 8.11, 3313.19 ± 210.16, and 19.16 ± 0.6, respectively. Bark C : N : P stoichiometry exhibited conspicuous latitudinal trends, with the exception of N : P ratios. These patterns were primarily shaped by the significant impacts of climate, soil conditions, and plant functional groups. However, the impact of evolutionary history in shaping bark C : N : P stoichiometry outweigh climate, soil, and plant functional group, aligning with the biogeochemical niche (BN) hypothesis. These finding enhance our understanding of the spatial distribution of bark nutrient stoichiometry and have important implications for modeling of global forest ecosystem nutrient cycles in a changing environment. [ABSTRACT FROM AUTHOR]

• The mechanism of carbonation of steel slag was explored. • Process simultaneously carbon sequestration, CO 2 capture and waste heat recovery. • Directly use the lime kiln gas as the gas source without purification. • Average treatment cost of 0.68 MWh for 1 t of steel slag for the process. The iron and steel-making industries have garnered significant attention in research related to low-carbon transitions and the reuse of steel slag. This industry is known for its high carbon emissions and the substantial amount of steel slag it generates. To address these challenges, a waste heat recovery process route has been developed for molten steel slag, which integrates CO 2 capture and fixation as well as efficient utilization of steel slag. This process involves the use of lime kiln flue gas from the steel plant as the gas quenching agent, thereby mitigating carbon emissions and facilitating carbonation conversion of steel slag while simultaneously recovering waste heat. The established carbonation model of steel slag reveals that the insufficient diffusion of CO 2 gas molecules within the product layer is the underlying mechanism hindering the carbonation performance of steel slag. This finding forms the basis for enhancing the carbonation performance of steel slag. The results of Aspen Plus simulation indicate that 1 t of steel slag (with a carbonation conversion rate of 15.169 %) can fix 55.19 kg of CO 2 , process 6.08 kmol of flue gas (with a carbon capture rate of 92.733 %), and recover 2.04 GJ of heat, 0.43 GJ of exergy, and 0.68 MWh of operating cost. These findings contribute to the development of sustainable and efficient solutions for steel slag management, with potential applications in the steel production industry and other relevant fields. [ABSTRACT FROM AUTHOR]

• Microscale crystallization phenomena of waste slag is explored visually. • Effect of homogeneous nucleation on thermal treatment of waste slag is substantial. • Crystal growth mode is various as the isothermal temperature increased. • Correlations are obtained to predict the microscale crystallization phenomena. Metal smelting and combustion of solid fuels produce significant quantities of waste slag, leading to issues such as land occupation and environmental pollution. Understanding and controlling the microscale crystallization phenomena of these slags during thermal treatment is crucial for transforming waste slags into materials suitable for carbon capture or glass ceramics. Previous research has primarily focused on macroscopic crystallization behaviors, significantly advancing the utilization of waste slags in cement clinker production. However, macroscopic results are inadequate for precisely controlling the microscale crystallization behaviors of waste slags. Here, we employed the single hot thermocouple technique to visually explore crystal growth modes, shapes, sizes, numbers, and translational rates of the crystal growth front in a representative blast furnace slag under various isothermal temperatures. The results revealed that crystals exhibited five modes as the isothermal temperature gradually increased, including equiaxed, equiaxed & columnar, columnar, columnar & planar, and planar. Moreover, the translational rate of the crystal growth front increased from 0.011 μm·s−1 to 43.7 μm·s−1 with an increase in the isothermal temperature. Simultaneously, the number of crystals decreased from around 104 to 100 μm−2. On this basis, correlations between microscale crystallization behaviors and isothermal temperature were established to fill the current gap. [ABSTRACT FROM AUTHOR]

The removal of atmospheric carbon dioxide (CO2) is now essential to meet net zero goals and limit the impacts of climate change. Enhanced weathering is a method of sequestering CO2 that involves the distribution of finely ground silicate rocks over agricultural land. The weathering of these silicate rocks releases cations into solution which can balance dissolved inorganic carbon, effectively removing CO2 from the atmosphere. Despite being a promising method of carbon dioxide removal (CDR), enhanced weathering has been limited by uncertainty surrounding the measurement of CO2 sequestration. This study compares current measurement approaches that focus on quantifying inorganic carbon and cations within the soil and leachate. Cation-based calculations of CDR were compared to inorganic carbon-based calculations of CDR and soil results were compared to leachate results. The recovery rate of cations in the soil fraction was also tested. Three different ground silicate minerals/rocks - basalt, olivine and wollastonite, were mixed with two different soils and were allowed to weather over 16 weeks in 320 pots with and without plants under different watering regimes and the application of an acidifying fertiliser. Soil and leachate samples were analysed for cations by ICP-OES and inorganic carbon by direct CO2 analysis after acidification and total alkalinity titration (in leachate only). The results indicate that the soil retains most enhanced weathering products through the cation exchange reactions. CDR estimated by cations is often greater than CDR estimated by inorganic carbon. Measurement approaches to estimate cations are susceptible to incomplete or improper accounting through the under-extraction of cations stored within the soil-exchangeable pool, the activity of non-carbonic acids and CO2 outgassing. Inorganic carbon-based measurements, including direct inorganic carbon and total alkalinity analysis, are also complicated by the potential for CO2 loss through carbonate precipitation and re-equilibration. Therefore, inorganic carbon-based approaches and cation-based approaches should be reconciled to validate the estimation of CDR. The inorganic carbon-based estimation of CDR in leachate should equal the cation-based estimation of CDR in leachate--which will be achieved after quantification or estimation of the natural mechanisms that affect each approach. These findings will support the development of accurate measurement processes for enhanced weathering. [ABSTRACT FROM AUTHOR]

The ultimate driver of the end-Permian mass extinction is a topic of much debate. Here, we used a multiproxy and paleoclimate modeling approach to establish a unifying theory elucidating the heightened susceptibility of the Pangean world to the prolonged and intensified El Niño events leading to an extinction state. As atmospheric partial pressure of carbon dioxide doubled from about 410 to about 860 ppm (parts per million) in the latest Permian, the meridional overturning circulation collapsed, the Hadley cell contracted, and El Niños intensified. The resultant deforestation, reef demise, and plankton crisis marked the start of a cascading environmental disaster. Reduced carbon sequestration initiated positive feedback, producing a warmer hothouse and, consequently, stronger El Niños. The compounding effects of elevated climate variability and mean state warming led to catastrophic but diachronous terrestrial and marine losses. [ABSTRACT FROM AUTHOR]

In addition to providing private goods such as food, fibre and biomass, agriculture can deliver a variety of environmental public goods and ecosystem services, such as biodiversity conservation, water filtering, carbon sequestration, and landscape aesthetics for recreation. Often, however, the use of agricultural landscapes prioritises the provision of private goods, resulting in negative environmental impacts. To address this imbalance in the provision of private and public goods, targeted policy instruments (e.g. contracts) are required to ensure that public goods are provided at the level desired by society. This paper, which is written in the context of the Horizon 2020 project “Contracts 2.0 – H2020 RUR-03-2018”, aims to present a Living Lab case study in Tuscany to point out possible future scenarios of contractual solutions that could provide the right incentives for farmers and land managers to produce a specific environmental public good such as agro-biodiversity. This paper aims to evaluate the application of Living Labs in the case study, assessing what challenges might seriously hinder the collaboration process and/or the success of the participatory approach. Thanks to the participatory approach, it was possible to finalise the “dream contract” in the Living Lab case study. Contract Innovation Labs and Policy Innovation Labs members agreed on a new type of contract based on clear and measurable objectives decided together by farmers and public authorities. [ABSTRACT FROM AUTHOR]

This study developed an energy-efficient, sustainable, and economical method for capturing carbon dioxide using landfilled coal fly ash. The innovative approach processes captured carbon dioxide with supplementary additives and alkali activators to produce a new class of hydraulic cement. A total of eight cement formulations incorporating varying proportions of landfilled coal fly ash, calcium-containing industrial byproducts, and alkali activators were produced and experimentally tested. The study achieved significant CO₂ uptakes, reaching up to 8.35% by weight of the raw materials. Up to 99.98% immobilization efficiency of heavy metal (copper) was recorded along with a significant increase in the total dissolved solids and conductivity. FTIR spectroscopy confirmed CO₂ incorporation with notable peaks at 1400 cm− 1 and 1063 cm− 1, indicating carbonate species. SEM and EDS analyses revealed varied morphologies, with dense, interconnected particle networks in some of the cement formulations. Compressive strength tests showed all formulations exceeded the EPA’s minimum requirement of 0.34 MPa, with the highest strength reaching 38 MPa at 28 days. The findings of this study point to the viability of the production of mechanochemically processed hydraulic cements in CO₂ environment with effective carbon sequestration capability, marked heavy metals immobilization characteristics, and enhanced physical and mechanical attributes. [ABSTRACT FROM AUTHOR]

Rechargeable lithium‐carbon dioxide (Li‐CO2) batteries present a compelling strategy for carbon capture and utilization techniques. Nevertheless, the formation of Li2CO3 as the main discharge product in the 4e−/3CO2 electrochemistry of Li‐CO2 batteries necessitates an elevated applied voltage to achieve full decomposition, which leads to severe performance issues in Li‐CO2 batteries. In this work, a stable lithium oxalate (Li2C2O4) electrochemistry involving a 2e−/2CO2 process triggered by Mo2N@Ti3C2O2 electrocatalyst is proposed, which facilitates highly reversible redox reactions in Li‐CO2 batteries. The presence of enriched ‐O terminations at the interface between Mo2N and Ti3C2O2 strengthens charge redistribution of Mo 3d orbital electron and enhances the coupling between Mo 3d orbitals and O 2p orbitals in Li2C2O4. The adsorption energy of Li2C2O4 on Mo2N@Ti3C2O2 surface and energy barrier for self‐disproportionation reaction of Li2C2O4 are further increased, enabling the stable Li2C2O4 electrochemistry. Therefore, the Mo2N@Ti3C2O2 based Li‐CO2 battery can produce Li2C2O4 discharge products even at a high discharge rate of 500 mA g−1 (ten times to previous studies) and during deep cycling processes. Due to the stable Li2C2O4 electrochemistry, Li‐CO2 batteries exhibit excellent electrochemical performance, including ultra‐low overpotential (0.55 V), ultra‐high energy efficiency (82.9%), and excellent cycling stability electrode (800 h). [ABSTRACT FROM AUTHOR]

Green hydrogen produced from water electrolysis using excess renewable electricity is not only a clean fuel but also an important chemical feedstock vital for global decarbonization and a circular carbon economy achieved through carbon dioxide capture and conversion. Transition metal dichalcogenides have recently emerged as efficient and low-cost electrocatalysts for sustainable green hydrogen production because they exhibit hydrogen binding energies comparable to platinum group metals, outstanding electrocatalytic activities, and high electrochemical stabilities over continued operation in the acidic medium. This article focuses on the synthesis, properties, and applications of ternary transition metal dichalcogenides in hydrogen evolution reaction with emphasis on structure – composition – activity relationships. Ternary transition metal dichalcogenides can either consist of two types of transition metals and a single chalcogen element or a single transition metal with two types of chalcogen elements. This allows numerous opportunities for fine-tuning of active sites, chalcogen substitutions, heteroatom doping, particle morphologies, and phase compositions to achieve optimal electrocatalytic activity, charge transfer resistance, porosity, and hydrogen evolution reaction kinetics. Molybdenum-based ternary transition metal dichalcogenides were identified to exhibit superior catalytic activity, stability, and cost-effectiveness compared to other transition metal dichalcogenides. [Display omitted] • Green hydrogen from electrocatalytic water splitting - HER. • Ternary TMDs and their composites as efficient and low-cost electrocatalysts for HER. • Ternary TMDs allow fine-tuning of properties for optimal HER activity. • Advancement in Mo, W, V, Ni, and Co TMDs' structure-activity relationships. • Mo-based ternary TMDs exhibit comparatively superior catalytic activity towards HER. [ABSTRACT FROM AUTHOR]

This study investigates the carbon offset potential in Espoo, Finland, by comparing a construction-impacted deforestation site with a larger conserved forest area. Addressing a knowledge gap in localized forest conservation as a CO2 offset method, our research quantifies the carbon stock and sequestration impacts under both baseline and alternative scenarios for the two study sites. The baseline scenario for offset site reflects standard forest management practices, while the alternative scenario involves complete forest conservation without active management. Our findings reveal that the conserved forest (79 ha), dominated by Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), increased its carbon stock by 26 Mg C ha-1 in soil and 65 Mg C ha-1 in biomass. This enhancement is sufficient to compensate for the smaller deforestation site's (19 ha), also containing a mix of Norway spruce and Scots pine, stock loss of 186 Mg C ha-1 in soil and 43 Mg C ha-1 in biomass. Furthermore, this study illuminates the complexities of CO2 compensation regulation and emphasizes the necessity for robust, transparent carbon accounting practices. The insights offer a valuable perspective on integrating nature-based solutions in urban planning to achieve broader ecological and climate goals. [ABSTRACT FROM AUTHOR]

CO2 emission reduction of sectors such as aviation, maritime shipping, road haulage, and chemical production is challenging but necessary. Although these sectors will most likely continue to rely on carbonaceous energy carriers, they are expected to gradually shift away from fossil fuels. In order to do so, the prominent option is to utilize alternative carbon sources--like biomass and CO2 originating from carbon capture--for the production of non-fossil carbonaceous vectors (biofuels and e-fuels). However, the limited availability of biomass and the varying nature of other carbon sources necessitate a comprehensive evaluation of trade-offs between potential carbon uses and existing sources. Then, it is primordial to understand the origin of carbon used in sustainable aviation fuel (SAF) to understand the implications of defossilizing aviation for the energy system. Moreover, the production of SAF implies deep changes to the energy system that are quantified in this work. This study utilizes the linear programming cost optimization tool EnergyScope TD to analyze the holistic French energy system, encompassing transport, industry, electricity, and heat sectors while ensuring net greenhouse gas neutrality. A novel method to model and quantify carbon flows within the system is introduced, enabling a comprehensive assessment of greenhouse gas neutrality. This study highlights the significance of fulfilling clean energy requirements and implementing carbon dioxide removal measures as crucial steps toward achieving climate neutrality. Indeed, to reach climate neutrality, a production of 1,046 TWh of electricity by non-fossil sources is needed. Furthermore, the findings underscore the critical role of efficient carbon and energy valorization from biomass, providing evidence that producing fuels by combining biomass and hydrogen is optimal. The study also offers valuable insights into the future cost and impact of SAF production for air travel originating from France. That is, the European law ReFuelEU would increase the price of plane tickets by +33% and would require 126 TWh of hydrogen and 50 TWh of biomass to produce the necessary 91 TWh of jet fuel. Finally, the implications of the assumption behind the production of SAF are discussed. [ABSTRACT FROM AUTHOR]

The potential of Euglena gracilis for carbon sequestration offers significant opportunities in the capture and utilization of carbon dioxide (CO2 ). In this study, a mutant LE-ZW of E. gracilis, capable of efficient growth and carbon sequestration, was obtained through ultraviolet mutagenesis combined with high carbon acclimation. Subsequently, the potential of LE-ZW for carbon assimilation was systematically analyzed. The results demonstrated that the cell density of the LE-ZW was 1.33 times that of the wild type and its carbon sequestration efficiency was 6.67 times that of the wild type when cultured at an optimal CO2 concentration of 5% until day 10. At this time, most key enzyme genes associated with the photosystem membrane protein complex, photosynthetic electron transport chain, antenna protein, and carbon fixation were up-regulated in mutant LE-ZW. Furthermore, after 10  days of culture under 10% CO2, the cell density and carbon sequestration efficiency of LE-ZW reached 1.10 times and 1.54 times of that under 5% CO2, respectively. Transcriptome analysis revealed significant up-regulation of key enzyme genes associated with carbon fixation, central carbon metabolism, and photosynthesis in LE-ZW under a 10% CO2 concentration. Physiological indices such as the amount of oxygen evolution, the values of Fv/Fm, the expression levels of photosynthetic protein genes and the enzyme activity of key enzymes related to photosynthetic carbon assimilation were corroborated by transcriptome data, elucidating that the mutant LE-ZW exhibited augmented photosynthetic carbon sequestration capacity and metabolic activity, thereby demonstrating robust adaptability to a high-carbon environment. This research contributes to a deeper understanding of the carbon assimilation mechanism in photosynthetic protists under elevated CO2 concentrations. [ABSTRACT FROM AUTHOR]

Introduction: The emergence of voluntary carbon markets is creating new opportunities to sustainably finance Natural Climate Solution (NCS) projects. In Australia, the federal government recently enacted the Tidal Restoration of Blue Carbon Ecosystems Methodology Determination 2022 (Tidal Reconnection Method), whereby restoration activities that reintroduce tidal flows to allow the re-establishment of coastal wetland (blue carbon) ecosystems, through the removal or modification of a tidal restriction, can be used to gain and sell Australian carbon credit units. Australia has the highest net blue carbon wealth in the world, with 5%-11% of global carbon stocks, yet there is currently a lack of large-scale feasibility assessments and supporting methodologies to identify and prioritise sites with the greatest potential for NCS project implementation to help inform investment decisions. Methods: In this study, we applied a spatial Multi-Criteria Decision Analysis (MCDA) to identify, map, and prioritise potential sites for blue carbon coastal wetland restoration in South Australia that meet criteria outlined in the Tidal Reconnection Method. This study compared information on 1) predicted flooding extent following tidal reconnection and under sea level rise (SLR; present-day, 2050 and 2,100); 2) project implementation complexity (e.g. who possesses land tenure); and 3) carbon sequestration potential through predicted area of vegetation change under the above SLR scenarios. Results: Our results identified 64 sites of interest, of which 32 received an overall "high" prioritisation score of 3 or more out of 5. This equates to approximately 21,114 ha of high priority potential blue carbon restoration sites. Discussion: The MCDA enables development of a portfolio of viable restoration projects through a rapid "desktop" prioritisation of sites of interest, which can then guide investment in further detailed cost/benefit feasibility assessments. This study demonstrates an adaptable MCDA approach to map potential NCS projects at meaningful spatial scales and in-line with carbon market-based opportunities. [ABSTRACT FROM AUTHOR]

Machine learning (ML)‐guided polymer design and synthesis will enable the next‐generation membrane material discovery for CO2 capture. Herein, ML is leveraged to establish a structure‐performance relationship for the eco‐friendly poly(ethylene oxide) (PEO) membrane and guide its design for high‐efficacy CO2/N2 separation. Through a rational fragment representation method and knowledge sharing across membranes fabricated by different methods, the precise prediction of CO2/N2 separation performance for PEO membranes with high Pearson correlation coefficients (0.973 for permeability and 0.875 for selectivity) despite data scarcity is demonstrated. Expertise knowledge and external monomer databases are then utilized in a human‐in‐the‐loop workflow to effectively explore high‐performance PEO membranes in the design space. Several discovered thermally crosslinked PEO membranes achieve CO2/N2 separation performances close to the 2019 Robeson upper bound, which are promising for practical large‐scale carbon capture applications. Model interpretation techniques are employed to provide data‐driven insights into the design of PEO membranes for high‐efficacy CO2/N2 separation. Further life cycle assessment results reveal the outstanding advantage of discovered PEO membranes in terms of environmental friendliness. The work highlights the enormous potential of ML in expediting the discovery of high‐performance carbon capture membrane materials. [ABSTRACT FROM AUTHOR]

Hollow fibre membrane (HFM) is favourable for carbon dioxide (CO2) due to its high packing density and high volume to area ratio. In this study, the effect of air gap and bore fluid ratio is explored to study its influence on the morphology and separation performance. With high dope extrusion rate (DER), the shear‐induced polymer orientation can be preserved with low air gap which come with the cost of deformed lumen. As such, the coagulant activity of the bore fluid can be reduced by introducing solvent, which in turn reduces rate of phase inversion to prevent sudden contraction of polymer at low air gap, thus allowing proper formation of lumen. With the presence of solvent, the flowability of the dope solution increased due to reduced viscosity as the bore fluid with high solvent content make contact the external coagulant. HFM spun with low air gap with the presence of solvent in the bore fluid shows increased stretched ratio due to the influence of gravitational pull upon being extruded from the spinneret. This in turn improved the polymer chain orientation due to the stretch across the spinning line. Subsequently, HFM spun with 80 wt.% of N‐methyl‐2‐pyrollidone (NMP) in the bore fluid using narrow gap spinneret with 5‐cm air gap shows the highest ideal CO2/N2 and CO2/CH4 selectivity at 23.4 and 28 respectively, even though it also exhibit the lowest CO2 permeance at only 3.1 GPU which was ascribed to the formation of dense skin layer. Meanwhile, when HFM was spun with a bigger annulus gap, the ideal CO2/N2 and CO2/CH4 selectivity slightly dropped, however the CO2 permeance exhibit increment. [ABSTRACT FROM AUTHOR]

Adsorption-based direct air carbon capture and storage (DACCS) is an emerging approach to mitigate climate change by removing CO2 from the atmosphere. Recent studies show separately that thermodynamic and environmental performance strongly depend on regional ambient conditions and energy supply but neglect regional CO2 storage potentials. To assess DACCS performance holistically, a detailed global analysis is needed that accounts for the interplay of regional ambient conditions, energy supply, and CO2 storage potential. Hence, we present a novel method for the optimal siting of DACCS plants derived from optimising a dynamic process model that uses global hourly weather data and regionalised data on electricity supply and CO2 storage potential. The carbon removal rate (CRR) measures the climate benefit and describes the speed at which a DACCS plant generates net negative emissions. First, we assume that CO2 storage is possible everywhere. For four electricity supply scenarios, we show that the optimal siting of DACCS significantly increases the CRR when comparing the best and worst locations in each scenario: For a DACCS plant with a nameplate capture capacity of 4 kt CO2 y−1, the CRR can be increased by 63% from 2.16 to 3.53 kt CO2 y‑1 when using photovoltaic, and by 39% from 2.95 to 4.1 kt CO2 y‑1 when using wind power. Assuming a carbon-free electricity supply, the CRR varies between 3.17 and 4.17 kt CO2 y‑1 (32%). Second, we significantly narrow down optimal locations for DACCS considering regional CO2 storage potential through CO2 mineralisation. Overall, accounting for the interplay of regional DAC performance, energy supply, and CO2 storage potential can significantly improve DACCS siting. [ABSTRACT FROM AUTHOR]

Supercapacitors are emerging as energy-efficient and robust devices for electrochemical CO2 capture. However, the impacts of electrode structure and charging protocols on CO2 capture performance remain unclear. Therefore, this study develops structure-property-performance correlations for supercapacitor electrodes at different charging conditions. We find that electrodes with large surface areas and low oxygen functionalization generally perform best, while a combination of micro- and mesopores is important to achieve fast CO2 capture rates. With these structural features and tunable charging protocols, YP80F activated carbon electrodes show the best CO2 capture performance with a capture rate of 350 mmolCO2 kg–1 h–1 and a low electrical energy consumption of 18 kJ molCO2–1 at 300 mA g–1 under CO2, together with a long lifetime over 12000 cycles at 150 mA g–1 under CO2 and excellent CO2 selectivity over N2 and O2. Operated in a "positive charging mode", the system achieves excellent electrochemical reversibility with Coulombic efficiencies over 99.8% in the presence of approximately 15% O2, alongside stable cycling performance over 1000 cycles. This study paves the way for improved supercapacitor electrodes and charging protocols for electrochemical CO2 capture. Supercapacitors are emerging as energy-efficient devices for CO2 capture. This work investigates the effects of charging protocols and electrode structures on electrochemical CO2 capture and explores the potential of devices for practical CO2 capture, especially in the presence of O2. [ABSTRACT FROM AUTHOR]

Reactive capture of carbon dioxide (CO2) offers an electrified pathway to produce renewable carbon monoxide (CO), which can then be upgraded into long-chain hydrocarbons and fuels. Previous reactive capture systems relied on hydroxide- or amine-based capture solutions. However, selectivity for CO remains low (<50%) for hydroxide-based systems and conventional amines are prone to oxygen (O2) degradation. Here, we develop a reactive capture strategy using potassium glycinate (K-GLY), an amino acid salt (AAS) capture solution applicable to O2-rich CO2-lean conditions. By employing a single-atom catalyst, engineering the capture solution, and elevating the operating temperature and pressure, we increase the availability of dissolved in-situ CO2 and achieve CO production with 64% Faradaic efficiency (FE) at 50 mA cm−2. We report a measured CO energy efficiency (EE) of 31% and an energy intensity of 40 GJ tCO−1, exceeding the best hydroxide- and amine-based reactive capture reports. The feasibility of the full reactive capture process is demonstrated with both simulated flue gas and direct air input. The electrosynthesis of CO via integrated capture and conversion of dilute CO2 suffers from low energy efficiency. Here, the authors report an amino acid salt-based system that employs a single-atom catalyst and operates at an elevated temperature and pressure, which enables efficient CO production. [ABSTRACT FROM AUTHOR]

Hydrogen is an abundant element and a flexible energy carrier, offering substantial potential as an environmentally friendly energy source to tackle global energy issues. When used as a fuel, hydrogen generates only water vapor upon combustion or in fuel cells, presenting a means to reduce carbon emissions in various sectors, including transportation, industry, and power generation. Nevertheless, conventional hydrogen production methods often depend on fossil fuels, leading to carbon emissions unless integrated with carbon capture and storage solutions. Conversely, green hydrogen is generated through electrolysis powered by renewable energy sources like solar and wind energy. This production method guarantees zero carbon emissions throughout the hydrogen's lifecycle, positioning it as a critical component of global sustainable energy transitions. In Africa, where there are extensive renewable energy resources such as solar and wind power, green hydrogen is emerging as a viable solution to sustainably address the increasing energy demands. This research explores the influence of policy frameworks, technological innovations, and market forces in promoting green hydrogen adoption across Africa. Despite growing investments and favorable policies, challenges such as high production costs and inadequate infrastructure significantly hinder widespread adoption. To overcome these challenges and speed up the shift towards a sustainable hydrogen economy in Africa, strategic investments and collaborative efforts are essential. By harnessing its renewable energy potential and establishing strong policy frameworks, Africa can not only fulfill its energy requirements but also support global initiatives to mitigate climate change and achieve sustainable development objectives. [ABSTRACT FROM AUTHOR]

This study examines the integration of emerging engineering technologies into STEM education with a focus on the green energy transition. Using a mixed-methods approach, including an international student survey conducted via Google Forms, the research identifies key factors influencing the demand for an innovative Master's program in Green Energy. Quantitative analysis through JASP software reveals a significant positive correlation between student interest in renewable energy related MSc courses and the perception of improved job opportunities in the green energy sector. Furthermore, the survey results indicate that students prioritize the inclusion of Mechanical, Electrical, and IT skills in the curriculum. Qualitative feedback highlights the critical need for practical skills in new research areas such as nanotechnology, quantum chemistry, Carbon capture, and Solar/Wind-based energy sources to meet the evolving demands of the green energy industry. These findings suggest that academic programs must be restructured to align more closely with the skills required for sustainable energy systems, thereby bridging the gap between academic preparation and market readiness. [ABSTRACT FROM AUTHOR]

The fast developing world is in search of measures to control the accumulation of unused by‐products and waste materials generated during the production of useful commodities. Accordingly, wastes from agro‐industrial sectors can form raw materials for the production of various resources that are extensively used in many areas such as gas sorption and energy production. In the present work, cashew nut shell liquid (CNSL), the vesicant liquid present in the outer shell of cashew seed, forms the source material for the synthesis of porous organic polymers for carbon dioxide capture. Herein, novel types of hypercrosslinked polymers (HCPs) are synthesized via a simple Friedel–Crafts reaction with CNSL as the starting material. Polymerization of natural CNSL with dimethoxymethane/bis‐(chloromethyl)‐biphenyl as external crosslinker provides products in quantitative yield. One of the synthesized HCP is tuned to attain the required high porosity by carbonization at elevated temperatures using an activator. Thus, activated carbon material prepared at 700°C is found to have a high surface area of 880 m2/g with a good carbon dioxide adsorption capacity of 14.72 wt%. These porous materials had moderate isosteric heat of adsorption (23–31 kJ/mol) with excellent recycling capability. [ABSTRACT FROM AUTHOR]

Most deep-ocean life relies on organic carbon from the surface ocean. While settling primary production rapidly attenuates in the water column, pulses of organic material can be quickly transported to depth in the form of food falls. One example of fresh material that can reach great depths across the tropical Atlantic Ocean and Caribbean Sea is the pelagic macroalgae Sargassum. However, little is known about the deep-ocean organisms able to use this food source. Here, we encountered the isopod Bathyopsurus nybelini at depths 5002–6288 m in the Puerto Rico Trench and Mid-Cayman Spreading Center using the Deep Submergence Vehicle Alvin. In most of the 32 observations, the isopods carried fronds of Sargassum. Through an integrative suite of morphological, DNA sequencing, and microbiological approaches, we show that this species is adapted to feed on Sargassum by using a specialized swimming stroke, having serrated and grinding mouthparts, and containing a gut microbiome that provides a dietary contribution through the degradation of macroalgal polysaccharides and fixing nitrogen. The isopod's physiological, morphological, and ecological adaptations demonstrate that vertical deposition of Sargassum is a direct trophic link between the surface and deep ocean and that some deep-sea organisms are poised to use this material. [ABSTRACT FROM AUTHOR]

MXenes, a class of two‐dimensional transition metal carbides, nitrides, and carbonitrides, have garnered significant attention due to their remarkable potential for energy storage, electrocatalysis, and gas separation applications. The fabrication processes of MXene involve building up the MXene structure from constituent elements and the selective elimination of M−A bonds from the precursor MAX. However, considerable efforts are still required to design and develop efficient MXene‐based technologies. This review article aims to briefly analyse the synthesis methods employed for MXene production, ranging from direct synthesis and conventional chemical wet etching approach to the more recent molten salt etching technique. The review highlights the advancements made in achieving precise control over the terminal groups, which is paramount for tailoring the properties of MXenes for specific applications. Furthermore, the potential of MXene‐based materials for carbon capture applications, particularly in developing advanced adsorbents, is emphasized. The in‐depth examination of MXene synthesis techniques and their implications for carbon capture applications provides a solid foundation for developing and optimizing these promising materials. [ABSTRACT FROM AUTHOR]

Background: Clostridium autoethanogenum is an acetogenic bacterium that autotrophically converts carbon monoxide (CO) and carbon dioxide (CO2) gases into bioproducts and fuels via the Wood–Ljungdahl pathway (WLP). To facilitate overall carbon capture efficiency, the reaction stoichiometry requires supplementation of hydrogen at an increased ratio of H2:CO to maximize CO2 utilization; however, the molecular details and thus the ability to understand the mechanism of this supplementation are largely unknown. Results: In order to elucidate the microbial physiology and fermentation where at least 75% of the carbon in ethanol comes from CO2, we established controlled chemostats that facilitated a novel and high (11:1) H2:CO uptake ratio. We compared and contrasted proteomic and metabolomics profiles to replicate continuous stirred tank reactors (CSTRs) at the same growth rate from a lower (5:1) H2:CO condition where ~ 50% of the carbon in ethanol is derived from CO2. Our hypothesis was that major changes would be observed in the hydrogenases and/or redox-related proteins and the WLP to compensate for the elevated hydrogen feed gas. Our analyses did reveal protein abundance differences between the two conditions largely related to reduction–oxidation (redox) pathways and cofactor biosynthesis, but the changes were more minor than we would have expected. While the Wood–Ljungdahl pathway proteins remained consistent across the conditions, other post-translational regulatory processes, such as lysine-acetylation, were observed and appeared to be more important for fine-tuning this carbon metabolism pathway. Metabolomic analyses showed that the increase in H2:CO ratio drives the organism to higher carbon dioxide utilization resulting in lower carbon storages and accumulated fatty acid metabolite levels. Conclusions: This research delves into the intricate dynamics of carbon fixation in C. autoethanogenum, examining the influence of highly elevated H2:CO ratios on metabolic processes and product outcomes. The study underscores the significance of optimizing gas feed composition for enhanced industrial efficiency, shedding light on potential mechanisms, such as post-translational modifications (PTMs), to fine-tune enzymatic activities and improve desired product yields. [ABSTRACT FROM AUTHOR]

Marsh and mangrove forest habitats are productive at capturing and storing carbon, thus actions to protect and create coastal blue carbon sinks could help mitigate global warming. Dredged material is often used to create coastal habitats and evaluating the carbon impact of placement alternatives (PA) could help inform restoration and climate policies. Output from a Delft3D‐FM morphodynamics and hydrodynamics model informed a Coastal Wetlands Carbon Model at years 2020, 2025, 2030, and 2050. Three model simulations were used and included (1) no restoration (PA1), (2) restoration dominated with mangroves (PA2), and (3) restoration dominated with marshes (PA3) at a different location. Habitats of brackish marsh, saline marsh, mangrove forest, and saline open water that surround Port Fourchon, Louisiana, U.S.A., were evaluated to estimate the net greenhouse gas (GHG) flux of the study area with and without restoration. In years 2020 and 2025, the study area was estimated to be a net GHG sink (−1.1 ± 0.2 MMT CO2e) with or without mangrove and marsh‐dominated restoration. At years 2030 and 2050, even with habitat loss due to sea‐level rise, the study area for all simulations was projected to remain a net GHG sink. At year 2050, +0.1 ± 0.04 MMT CO2e could be avoided with restoration. At the restoration project scale, mangrove‐dominated restoration (PA2) had net GHG sinks (−0.07 to −0.09 MMT CO2e) near the marsh‐dominated restoration (PA3, −0.09 to −0.13 MMT CO2e). Thus, these modeled results could help inform future restoration planning and climate policies. [ABSTRACT FROM AUTHOR]

Creating an innovative and environmentally friendly energy storage system is of vital importance due to the growing number of environmental problems and the fast exhaustion of fossil fuels. Energy storage using porous carbon composites generated from biomass has attracted a lot of attention in the research community. This is primarily due to the environmentally friendly nature, abundant availability in nature, accessibility, affordability, and long‐term viability of macro/meso/microporous carbon sourced from a variety of biological materials. Extensive information on the design and the building of an energy storage device that uses supercapacitors was a part of this research. This study examines both porous carbon electrodes (ranging from 44 to 1050 F/g) and biomasses with a large surface area (between 215 and 3532 m2/g). Supposedly, these electrodes have a capacitive retention performance of about 99.7 percent after 1000 cycles. The energy density of symmetric supercapacitors is also considered, with values between 5.1 and 138.4 Wh/kg. In this review, we look at the basic structures of biomass and how they affect porous carbon synthesis. It also discusses the effects of different structured porous carbon materials on electrochemical performance and analyzes them. In recent developments, significant steps have been made across various fields including fuel cells, carbon capture, and the utilization of biomass‐derived carbonaceous nanoparticles. Notably, our study delves into the innovative energy conversion and storage potentials inherent in these materials. This comprehensive investigation seeks to lay the foundation for forthcoming energy storage research endeavors by delineating the current advancements and anticipating potential challenges in fabricating porous carbon composites sourced from biomass. [ABSTRACT FROM AUTHOR]

Carbon Capture, Utilization, and Storage (CCUS) offers a viable solution to reduce the carbon footprint in the petroleum industry, and foam injection presents a promising method to achieve this while simultaneously increasing oil recovery. In this work, we studied the feasibility of CO2 foam for co-optimizing enhanced oil recovery and CO2 storage in a high-salinity carbonate formation. The simulated hydrodynamic model is a depleted formation containing 30% residual oil, with three mechanisms for CO2 storage: solubility, residual, and mineralization trapping mechanisms. The results showed that after 20 years, oil recovery during foam injection was 2.7 times higher than CO2 injection, and the CO2 stored during foam flooding was 38% higher than CO2 injection. Notably, foam injection also increased CO2 storage capacity by 2.6 times, indicating the potential to store around 2 gigatons of CO2 in the simulated model. This was attributed to the ability of foam to significantly reduce gas mobility and thus form isolated bubbles through its Jamin effect. Residual trapping was the dominant trapping mechanism, contributing to over 70% of the total CO2 trapped, attributed to the reduction in the dissolution of CO2 in brine due to the high salinity of the aqueous medium. CO2 mineralization was also studied, showing the least trapping efficiency and the dissolution trend of all the carbonate minerals. This study illustrates a novel CO2 utilization and storage technique in which CO2 is concurrently sequestered while enhancing oil recovery in a depleted oil reservoir by injecting CO2 as foam. The relevance of this study lies in its potential to provide a dual benefit of reducing greenhouse gas emissions and boosting oil production, offering a sustainable approach for the petroleum industry. [ABSTRACT FROM AUTHOR]

Summary Knowledge of differential life‐history strategies in arbuscular mycorrhizal (AM) fungi is relevant for understanding the ecology of this group and its potential role in sustainable agriculture and carbon sequestration. At present, AM fungal life‐history theories often focus on differential investment into intra‐ vs extraradical structures among AM fungal taxa, and its implications for plant benefits. With this Viewpoint we aim to expand these theories by integrating a mycocentric economics‐ and resource‐based life‐history framework. As in plants, AM fungal carbon and nutrient demands are stoichiometrically coupled, though uptake of these elements is spatially decoupled. Consequently, investment in morphological structures for carbon vs nutrient uptake is not in competition. We argue that understanding the ecology and evolution of AM fungal life‐history trade‐offs requires increased focus on variation among structures foraging for the same element, that is within intra‐ or extraradical structures (in our view a ‘horizontal’ axis), not just between them (‘vertical’ axis). Here, we elaborate on this argument and propose a range of plausible life‐history trade‐offs that could lead to the evolution of strategies in AM fungi, providing testable hypotheses and creating opportunities to explain AM fungal co‐existence, and the context‐dependent effects of AM fungi on plant growth and soil carbon dynamics. [ABSTRACT FROM AUTHOR]

The pursuit of high efficacy C−C coupling during the electrochemical CO2 reduction reaction remains a tremendous challenge owing to the high energy barrier of CO2 activation and insufficient coverage of the desired intermediates on catalytic sites. Inspired by the concept of capture‐coupled CO2 activation, we fabricated quinone‐grafted carbon nanofibers via an in situ oxidative carbonylation strategy. The quinone functionality of carbon nanofibers promotes the capture of CO2 followed by activation. At a current density of 400 mA cm−2, the Faradaic efficiency of ethylene reached 62.9 %, and a partial current density of 295 mA cm−2 was achieved on the quinone‐rich carbon nanofibers. The results of in situ spectroscopy and theoretical calculations indicated that the remarkable selectivity enhancement in ethylene originates from the quinone structure, rather than the electronic properties of Cu particles. The interaction of quinone with CO2 increases the local *CO coverage and simultaneously hinders the co‐adsorption of *H on Cu sites, which greatly reduces the energy barrier for C−C coupling and restrains subsequent *CO protonation. The modulation strategy involving specific oxygenated structure, as an independent degree of freedom, guides the design of functionalized carbon materials for tailoring the selectivity of desired products during the CO2 capture and reduction. [ABSTRACT FROM AUTHOR]

Hydrogen power and electric vehicle rollout are among the global mitigation efforts for net-zero emission targets. Hydrogen fuel cell vehicle (HFCV) is a promising embodiment of these two climate-neutral levers. Nevertheless, insufficient investigation of the life cycle of hydrogen production pathways and supply-demand mismatching jeopardize the optimal implementation of HFCV. A novel integrated framework combining life cycle greenhouse gas assessment and intra-regional supply-demand optimization method is developed to (1) evaluate the emissions performance for six typical HFCV hydrogen production pathways and (2) map out the optimal intra-regional hydrogen supply-demand allocation based on the trade-off between resource flow and geographical proximity. As one of the world's largest HFCV producers and consumers, China is chosen as the case study. The life cycle emissions assessment reveals that the Natural Gas Steam Methane Reforming (NG_SMR) pathway emits the most greenhouse gas (GHG) emissions (i.e., 0.215 g CO 2 -eq/kJ H 2) while the Clean Energy_Water Electrolysis (CE_WE) pathway emits the least GHG emissions (i.e., 0.02 g CO 2 -eq/kJ H 2), stretching a 10-times emission difference. For intra-regional supply-demand optimization, provinces like Shaanxi, Shanxi, and Shandong act as the main suppliers (>50% of the total hydrogen source in China) to provinces like Guangdong, Zhejiang, and Sichuan, suggesting a north-to-south (N-S) regional hydrogen transmission. A sensitivity analysis is conducted based on the variation in production efficiency among different hydrogen production technologies in the HFCV value chain. The results inferred that the Coal Gasification & Carbon Capture and Storage (C l G & CCS) and CE_WE pathways are insensitive to efficiency improvement. In the scenario analysis, the outcome suggested urgently phasing out grey hydrogen pathways and accelerating the transition of grey-to-green hydrogen production pathways with the buffering of blue hydrogen pathways between 2015 and 2040 for the net-zero emission ambition by 2060. This study enlightens the decision-makers to endorse green hydrogen production for HFCV while securing hydrogen energy security. [Display omitted] • Hydrogen fuel cell vehicles accelerate low carbon transition in transportation sector. • Hydrogen resource allocation is one of the challenges developing fuel cell vehicle. • Life cycle assessment and intra-regional supply-chain optimization are coupled. • The integrated framework suggests a north-to-south hydrogen delivery in China. • Blue hydrogen pathway serves as an intermediate between grey-to-green transition. [ABSTRACT FROM AUTHOR]

The electrification of chemical processes holds promise for a sustainable and climate-neutral chemical industry. This study explores pathways for electrifying syngas production, targeting its utilization in low-temperature Fischer-Tropsch (LT-FT) technology with a hydrocarbon production capacity of 222 kton/yr. Three electrified scenarios are juxtaposed against a reference case of autothermal reforming of biomethane. In the first two scenarios, H 2 is produced via water electrolysis, with CO obtained either through CO 2 electrolysis (Electrolysis case) or electrified reverse water-gas shift (E-rWGS case). The third scenario leverages captured CO 2 and biomethane for electrified combined steam and dry reforming of methane (CSDRM case), exhibiting the lowest net emissions of 0.50 ton CO2 /ton product. All electrified scenarios achieve net negative emissions under the EU's 2030 target of 40% overall renewable energy production. A detailed techno-economic analysis reveals significant feasibility challenges with the Electrolysis, E-rWGS, and CSDRM cases exhibiting a Levelized Cost Of Production (LCOP) of $501, $457, and $251 per barrel (bbl) of Fischer-Tropsch crude, respectively. Future projections suggest considerable capital cost reductions for electrolyzers, potentially rendering the Electrolysis case feasible, particularly under extremely low electricity prices of 3.3 $/MWh. Careful consideration of green electricity and CO 2 utilization scenarios is vital for implementing CO 2 -negative technologies effectively. [Display omitted] • Three layouts of electrified syngas production for FT synthesis are evaluated. • CSDRM leads at an LCOP of 251 $/bbl of FT crude, emitting 0.50 ton CO2 /ton product. • Electrolyzers can become cost-competitive for electricity price below 3.3 $/MWh. • Political support and advancements will dictate the viability of such options. [ABSTRACT FROM AUTHOR]

Blue hydrogen (H 2) serves as a pivotal initial step towards emissions reduction and a seamless transition to green hydrogen by providing a cleaner alternative to grey hydrogen. Blue H 2 can be obtained through diverse pathways (i.e. , distinct processes and stages) within the hydrogen supply network (HSN), resulting in varying greenhouse gas emission levels. This paper uses the Life Cycle Assessment methodology to compare 18 different blue HSN pathways. Blue hydrogen is produced from three different processes (i.e. , Steam Methane Reforming (SMR), Partial Oxidation of Methane (POM), and Auto-Thermal Reforming (ATR)) that are coupled with carbon capture unit (CCU). Moreover, it can be conditioned to different states or carriers (i.e. , liquefied H 2 , compressed H 2 , ammonia, and methanol), stored using various methods, transported by different means according to its state, and reconditioned to its original state at end-users. The LCA results indicate that the NH 3 pathway has the least environmental impact measuring just 2.12 kgCO 2equ / kgH 2 compared to the other 18 blue HSN pathways. This pathway involves producing hydrogen from ATR process coupled with CCS, and eventually delivering as ammonia to consumers. Additionally, the blue H 2 results of this paper are compared to the green H 2 results discussed in the previous paper. The comparison highlights that integrating renewable energy in the form concentrated photovoltaic collectors produces the lowest emissions compared to all pathways. It reduces the emissions from 45.3% to 67% depending on the pathways, compared to the ATR process coupled with CCU. • SMR, POM, or ATR with carbon capture for blue hydrogen production. • This LCA study compares 18 blue HSN pathways for their environmental performance. • Different pathways within the HSN lead to various levels of GHG emissions. • NH 3 path emits the least emissions (2.12 kgCO 2equ /kgH 2) among blue H 2 paths. • CH 2 path emits the least emissions (0.080 kgCO 2equ /kWh) among all paths. [ABSTRACT FROM AUTHOR]

The United States' focus on decarbonization has spawned interest among policymakers in deploying water electrolysis technology for clean hydrogen production. However, water electrolyzers also raise concerns regarding their substantial use of carbon-intensive materials. Here, we conduct a comprehensive life-cycle analysis (LCA) of three prominent water electrolyzer technologies to investigate the environmental implications of their manufacturing and life cycles under different energy sources. All electrolyzer technologies employing low-carbon energy (nuclear, solar, or wind) exhibit life-cycle greenhouse gas (GHG) emissions of 0.3–2.4 kg-CO 2-eq /kg-H 2. This is significantly lower than the corresponding GHG emissions for hydrogen production via both conventional steam methane reforming and alternative autothermal reforming with carbon capture and storage (by > 50%). The well-to-gate GHG emissions of low-carbon electrolyzers (0–0.36 kg-CO 2-eq /kg-H 2) qualify for Tier I of the production tax credit in the U.S.' Inflation Reduction Act of 2022, indicating their suitability for producing decarbonized hydrogen under this program. • Compares the life-cycle environmental impacts of SOEC, PEM, and AEC electrolyzers • Ni, Ti, Si, steel, Cu, and energy use dominate electrolyzers' manufacturing impacts • Electricity generation-related impacts dictate electrolyzers' life-cycle impacts • Low-carbon electrolysis outperforms other H 2 -producing technologies over life-cycle • Decarbonized H 2 production requires clean material production and low-carbon energy [ABSTRACT FROM AUTHOR]

Most of the implemented marine gas hydrate test exploitation in the world adopt the depressurization method to break down the hydrate in the reservoir into natural gas and then extract it, but because the gas production results are still a certain distance away from the commercial exploitation, and it mainly stays in the stage of theoretical research and trial exploitation. Based on two trial productions in the Shenhu area of the South China Sea, this study established a model for hydrate exploitation and investigated the impact of different well types on the recovery rates of hydrates and free gas in different development layers during depressurization. For the Class 1 hydrate reservoirs, horizontal wells are the optimal solution to extract hydrate and free gas simultaneously when exploiting the hydrate three-phase layer. Meanwhile, the effect of different well spacing in vertical wells on the recovery rate of hydrate and free gas was studied. It is found that the best recovery efficiency is achieved when the spacing between two wells is 80 m. The lower the bottom flow pressure of the well, the higher the production capacity, but its influence is limited. [ABSTRACT FROM AUTHOR]

Coastal marine habitats (i.e. mangroves, saltmarshes, and seagrasses) have a high capacity for carbon sequestration (termed "blue carbon") and the potential to reduce the effects of greenhouse gas emissions. However, blue carbon habitats have historically decreased as a consequence of land conversion, coastal development, and pollution and are under threat in many locations. Restoration of these habitats can reverse historic losses and generate carbon credits through increased carbon sequestration. With a long coastline, we hypothesized that there would be significant opportunities for coastal blue carbon in Aotearoa New Zealand. Results revealed Aotearoa estuaries and coastal areas contain approximately 20,932 ha of saltmarsh, 30,533 ha of mangrove, and 61,340 ha of seagrass, estimated to sequester a total of approximately 57,800 tC/year. A further 87,861 ha of land was estimated to be potentially suitable for blue carbon projects via tidal restoration, of which 56,482 ha was suitable for saltmarsh restoration (equivalent to 60,435 tC yr if restored), 17,291 ha was suitable for mangroves (26,455 tC/year), and 14,087 ha was suitable for seagrass (4790 tC/year). Both existing extent and restoration opportunity varied throughout the country, with greater opportunity in some regions than others. Nationwide, the total sequestration potential for blue carbon restoration was estimated at 91,680 tC yr−1 if all potential areas were restored. Carbon credits generated by blue carbon projects could be traded on a carbon market in Aotearoa, generate revenue for landowners, provide an additional pathway to meet domestic and international climate change targets, and result in a diversity of other ecological, social, and cultural co‐benefits from coastal restoration. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems play a crucial role in global carbon cycling by sequestering carbon from the atmosphere and storing it primarily in living biomass and soil. Monitoring terrestrial carbon stocks is essential for understanding the impacts of changes in land use on carbon sequestration. This study investigates the potential of remote sensing techniques and the Google Earth Engine to map and monitor changes in the forests of Calabria (Italy) over the past two decades. Using satellite-sourced Corine land cover datasets and the InVEST model, changes in Land Use Land Cover (LULC), and carbon concentrations are analyzed, providing insights into the carbon dynamics of the region. Furthermore, cellular automata and Markov chain techniques are used to simulate the future spatial and temporal dynamics of LULC. The results reveal notable fluctuations in LULC; specifically, settlement and bare land have expanded at the expense of forested and grassland areas. These land use and land cover changes significantly declined the overall carbon stocks in Calabria between 2000 and 2024, resulting in notable economic impacts. The region experienced periods of both decline and growth in carbon concentration, with overall losses resulting in economic impacts up to EUR 357.57 million and carbon losses equivalent to 6,558,069.68 Mg of CO   2 emissions during periods of decline. Conversely, during periods of carbon gain, the economic benefit reached EUR 41.26 million, with sequestered carbon equivalent to 756,919.47 Mg of CO   2 emissions. This research aims to highlight the critical role of satellite data in enhancing our understanding and development of comprehensive strategies for managing carbon stocks in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

A Carbon Footprint (CF) is defined as the total emissions of greenhouse gases, primarily carbon dioxide, methane, and nitrous oxide, and is a specific type of Environmental Footprint that measures human impact on the environment. Carbon dioxide emissions are a major contributor to anthropogenic greenhouse gases driving climate change. Wood, as a renewable and ecological material, has relatively low carbon emissions. The study aimed to review and analyze the criteria influencing the feasibility of constructing modern zero-carbon wooden buildings. The review was conducted in two phases: (i) a literature review and (ii) an assessment of existing buildings. The preliminary research led to (i) narrowing the focus to the years 2020–2024 and (ii) identifying key criteria for analysis: sustainable material sourcing, carbon sequestration, energy efficiency, life cycle assessment (LCA), and innovative construction practices. The study's findings indicate that all these criteria play a vital role in the design and construction of new zero-carbon wooden buildings. They highlight the significant potential of wood as a renewable material in achieving zero-carbon buildings (ZCBs), positioning it as a compelling alternative to traditional construction materials. However, the research also underscores that despite wood's numerous potential benefits, its implementation in ZCBs faces several challenges, including social, regulatory, and financial barriers. [ABSTRACT FROM AUTHOR]

Biomass gasification has emerged as a promising method for producing renewable energy, addressing both energy and environmental challenges. This review examines recent research on gasification simulations, covering a range of topics from process modeling to syngas cleanup. Key areas explored include techniques for syngas cleaning, addressing tar formation, and CO2 capture methods. The aim of this review is to provide an overview of the current state of gasification simulation and identify potential areas for future research and development. This work serves as an invaluable resource for researchers, engineers, and industry professionals involved in biomass gasification modeling. By providing a comprehensive guide to biomass gasification simulation using Aspen Plus software and comparing various modeling approaches, it assists users in selecting the most effective tool for optimizing the design and operation of gasification systems. [ABSTRACT FROM AUTHOR]

This study utilizes machine learning to quantify CO2 plume extents by analyzing microseismic data from the Illinois Basin Decatur Project (IBDP). Leveraging a unique dataset of well logs, microseismic records, and CO2 injection metrics, this work aims to predict the temporal evolution of subsurface CO2 saturation plumes. The findings illustrate that machine learning can predict plume dynamics, revealing vertical clustering of microseismic events over distinct time periods within certain proximities to the injection well, consistent with an invasion percolation model. The buoyant CO2 plume partially trapped within sandstone intervals periodically breaches localized barriers or baffles, which act as leaky seals and impede vertical migration until buoyancy overcomes gravity and capillary forces, leading to breakthroughs along vertical zones of weakness. Between different unsupervised clustering techniques, K-Means and DBSCAN were applied and analyzed in detail, where K-means outperformed DBSCAN in this specific study by indicating the combination of the highest Silhouette Score and the lowest Davies–Bouldin Index. The predictive capability of machine learning models in quantifying CO2 saturation plume extension is significant for real-time monitoring and management of CO2 sequestration sites. The models exhibit high accuracy, validated against physical models and injection data from the IBDP, reinforcing the viability of CO2 geological sequestration as a climate change mitigation strategy and enhancing advanced tools for safe management of these operations. [ABSTRACT FROM AUTHOR]

The thermal regeneration of CO2 sorbent is the most energy-consuming step in the CO2-capturing process. Although the addition of an acid can induce CO2 release, it does not regenerate the sorbent because the acid forms a salt with the basic sorbent and diminishes its capability for capturing CO2. In this work, a novel approach based on thermally enhanced acidity was studied. This approach utilizes an additive that does not affect the sorbent at room temperature, but its acidity significantly increases at elevated temperatures, which assists the thermal release of CO2. M-cresol was added to an aqueous solution of morpholine. The CO2 capture and release of the mixture were compared to those of a control solution without m-cresol. The amounts of carbamate, bicarbonate, and unreacted morpholine were quantitatively determined using 1H NMR and weight analysis. The results showed that m-cresol did not affect the reactivity of morpholine in the formation of carbamate with CO2 at room temperature. At elevated temperatures, the acidity of m-cresol increased according to Van't Hoff's equation, which resulted in a significantly higher rate of CO2 release than that of the control. Given the low cost of m-cresol and its derivatives, this approach could lead to practical technology in the near future. [ABSTRACT FROM AUTHOR]

CCUS technologies are crucial solutions for mitigating climate change by reducing CO2 emissions from industrial operations and energy sectors. This review critically examines the current state of CCUS technologies, and highlights advancements, challenges, regulatory frameworks, and future directions. It comprehensively analyzes carbon capture methods, such as pre-combustion, post-combustion, and oxy-fuel combustion capture, while comparing their efficiencies and limitations. The review also explores carbon utilization techniques, such as direct and indirect utilization, emphasizing their potential applications and technological constraints. Additionally, it assesses various carbon storage methods, focusing on geological, ocean, and mineralization storage, and discusses their capacity, feasibility, and environmental implications. The study reviews the policy and regulatory frameworks, economic viability, market trends, and environmental sustainability of CCUS. By identifying research gaps and recommending future research priorities, this review aims to guide the development of more efficient/effective, and cost-effective CCUS technology, ensuring their role in a sustaining low-carbon future. This review provides a forward-looking perspective, a critical and interdisciplinary analysis that assesses the current state of CCUS technologies, and further provides a roadmap for future development. [ABSTRACT FROM AUTHOR]