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Ion-selective membranes are necessary components of many electrochemical systems including fuel cells, electrolyzers, redox flow batteries, and electrodialyzers. Perfluorinated sulfonated membranes (PFSMs) dominate these applications due to their excellent combination of fast ion transport, stability, and processability. However, perfluorinated cation exchange membranes (CEMs) are expensive, and their production process involves chemistry that generates toxic perfluorinated chemicals. The development of affordable, nonfluorinated membranes with a competitive combination of high ion selectivity, transport, and stability could help enable the widespread use of the technologies listed above while hastening the development of emerging electrochemical systems, including aqueous alkaline CO2 sorbent regeneration. To this end, we pursue the use of thin-film composite polyamide (PA-TFCs) membranes─those that typically find application in reverse osmosis and nanofiltration desalination─as cation-selective exchange membranes. Given their negative surface charge under neutral-to-alkaline conditions, PA-TFCs can serve as effective CEMs in these pH regimes. We prepared a series of PA-TFCs from traditional monomers (trimesoyl chloride and piperazine) and compared their thicknesses, charge densities, water transport properties, ion transport properties, and long-term stability in a high pH environment to traditional CEMs (Nafion and FKE) and commercial nanofiltration and reverse osmosis membranes. We find that some of the best-performing PA-TFC membranes have similar resistances and Na+ transference numbers compared to Nafion 117 in Na2SO4 and NaHCO3-containing solutions. This proof-of-principle study suggests that further optimization of PA-TFCs could enable cost-effective ion exchange membrane alternatives to PFSMs.

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]

Industrial exhaust gases and gas fields are two significant sources of carbon dioxide (CO2) emissions that contribute to the rising levels of CO2 in the atmosphere. Among the various emission reduction systems, the CCSU (Carbon Capture, Storage, and Utilization) system has garnered extensive attention and research. This research aims to obtain the superstructure network sequentially in the CCSU system using GAMS (General Algebraic Modeling System). A mathematical approach was developed to optimize the amount of CO2 stored and utilized by varying the time difference (dt) between the source and sink from 0 to 10 years. After calculating the economic potential (EP), it was found that the Carbon Capture and Storage (CCS) system for both sources has a negative impact. In contrast, the CCSU system enhances the economic potential (EP) by generating a positive value. This is possible as the captured CO2 can be sold to the utilization sink, thereby creating a revenue stream. The EP for CO2 reduction from gas fields is greater than that from the industry, 21.68 × 106 USD compared to 12.50 × 106 USD at dt min10 years. The CCSU system, when utilizing CO2 sources from gas fields, is more profitable compared to using industrial emissions. [ABSTRACT FROM AUTHOR]

Technologies for capturing and storing carbon dioxide (CO2) and strategies for sequestering carbon dioxide have received a lot of interest in recent years as potential remedies for the curtailment of the growing concerns of emissions of greenhouse gases and global warming. This article provides a comprehensive analysis on the trends in research and development in the area of CO2 carbon capture and sequestration at the moment. The review explores various technological approaches for capturing CO2 from industrial emissions, such as post‐combustion capture systems, pre‐combustion capture systems, and oxy‐fuel combustion system. It also gives a major insight into the post‐combustion capture of carbon by means of a summary, information obtained via a personal interview with a Combustion Based Unit (CBU) plant manager. Additionally, different methods for storing and sequestering the aforementioned gas, including geological and oceanic archiving, and mineralization, are examined. By synthesizing the findings from a wide range of studies and research papers, this literature review provides valuable insights into the current technologies for CO2 capture, storage, and sequestration, contributing to the ongoing efforts in addressing climate change and achieving sustainable development goals. [ABSTRACT FROM AUTHOR]

In this study, the high potential tertiary N-methyl-4-piperidinol or MPDL (0.25–1.00 M) was blended with 5 M monoethanolamine (MEA) to formulate 5.25–6.00 M MEA-MPDL solvent and compare with the benchmark 5 M MEA. It was found that the density and the Henry's constant slightly decreased, while the viscosity increased as the MPDL concentration in the blend increased. Even though the equilibrium CO2-loaded viscosity considerably increased (by 34.3–40.2%) as the MPDL content increased, it was still in a great operating region of less than 10 mPa.s. Experimental overall reaction kinetics constant ( k ov ) was well corresponding with the zwitterion mechanism of MEA and the base-catalyze hydration mechanism of MPDL based absorption kinetics model, with %AAD of 0.56%. Interestingly, an addition of MPDL into 5 M MEA slightly enhanced k ov (1.2–3.3% increment) and considerably favored absorption capacity (13–31% elevation), and regeneration heat duty (28–47% reduction), respecting 5 M MEA. The proposed strategic blending can maintain the overall solvent reactivity at the same level of the benchmark, while obviously increase the absorption capacity and largely reduce the regeneration heat duty. This highly favors a solvent upgrading for the existing 5 M MEA based CO2 capture plant. According to the recent data, 5 M MEA + 1.00 M MPDL was suggested. Since the blend was formulated at high concentration, its corrosiveness should also be considered. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage (CCUS) technologies are an integral part of the carbon-neutral technology portfolio at the present phase. However, large-scale implementation of CCUS technologies may increase urban water consumption and raise urban water security issues. In this paper, 596 large-scale coal-fired power plants were investigated in terms of water withdrawal and water consumption. To minimize total water withdrawal and total water consumption, a source-sink matching model for CCUS projects under water resource constraints was established to optimize the layout of CCUS projects in China. The results show that there is a mismatch between the distribution of coal-fired power plants in a spatial location and water resources. The annual increase in water withdrawal of about 27.6 billion tons and water consumption of about 2.4 billion tons is needed to achieve the 2 °C target, which will aggravate the water scarcity in the north-central cities. Implementation of CO2-enhanced water recovery (CO2-EWR) technology can offset some of the increase in urban water consumption owing to CCUS deployment. This study can provide data support for site selection in the large-scale deployment of CCUS technology and provide the theoretical basis for decision-makers to lay out CCUS projects. [ABSTRACT FROM AUTHOR]

Nowadays, industries across the globe are acknowledging the need for a Net Zero Supply Chain (NZSC) by 2050, particularly within the Manufacturing Supply Chain (MSC) due to its significant contribution to Greenhouse Gas (GHG) emissions. Government and regulatory bodies pressure the industry to reduce GHG emissions. Industries focus on cleaner and sustainable production by adopting net zero technique practices. Achieving the net zero goal needs technological integration, such as Caron Capture Technology (CCT) and Life Cycle Assessment (LCA). Are LCA and CCT unlocking the potential for net-zero practices in MSC? This still needs to be answered. Therefore, this study aims to identify and prioritize potential enablers of Life Cycle Assessment (LCA) to facilitate the NZSC. We identified potential enablers using a Systematic Literature Review (SLR) and expert opinion. An empirical study validated these enablers, followed by the application of the "Best-Worst Method (BWM)" to rank them and the "Fuzzy Decision-making trial and evaluation laboratory (F-DEMATEL)" to identify causal relationships. The outcomes of this study reveal that 'Energy Management and Emission Reduction' is the most critical category of enablers, followed by 'Governance and Collaboration', 'Assessment and Digitalization', and 'Sustainable Materials and Production'. Outcomes highlight the importance of integrating technological innovations and stakeholder engagement to achieve net-zero goals. The implications of this study provide valuable insights for policymakers and practitioners. By focusing on the prioritized enablers, the manufacturing industry can effectively implement LCA, develop the NZSC business model, and enhance competitiveness in the global market. This study contributes to the ongoing discourse on sustainable manufacturing practices and offers a strategic framework for achieving NZSC by 2050. [ABSTRACT FROM AUTHOR]

Objective The aim is to solve the problems of high regeneration energy consumption and high economic cost in the capture of carbon dioxide(CO2) by traditional absorbents, and to develop new phase change absorbents. Methods This paper provided a comparative study of the performance of four phase change absorbent systems: DETA-1-propanol, MMEA-DEG, DEEA-MEA, and DEEA-AEEA. Using monoethanolamine (MEA) with a traditional absorbent mass fraction of 30% as a reference standard, experiments were conducted to study absorption, desorption, foaming, corrosion, cyclic absorption-desorption, as well as estimated regeneration energy consumption and costs. Results The DETA-1-propanol system had a rich phase volume accounting for 66% of the total volume, with a maximum absorption capacity of 3.34 mol/kg, representing a 54.6% improvement compared to 30% MEA absorbents. The solvent cost was 11 500 yuan/t, which increased by 35.5% compared to 30% MEA absorbents. The regeneration enthalpy was 0.28 GJ/t CO2, and the regeneration latent heat was 1.1 GJ/t CO2. Compared with MEA absorbent, it reduced by 73.3% and 12.0%, respectively. Conclusions The DETA-1-propanol absorbent system exhibits higher absorption and desorption performance, high cycling stability, as well as lower regeneration energy consumption and solvent cost. [ABSTRACT FROM AUTHOR]

• In-situ BMED-CCUS realized high-value utilization of saline water and carbon as Na 2 CO 3. • Process parameters was optimized to improve carbon fixation performance and product quality. • This system outperforms the ex-situ method in process efficiency and integrity. In the context of carbon capture, utilization, and storage, the high-value utilization of carbon storage presents a significant challenge. To address this challenge, this study employed the bipolar membrane electrodialysis integrated with carbon utilization technology to prepare Na 2 CO 3 products using simulated seawater concentrate, achieving simultaneous saline wastewater utilization, carbon storage and high-value production of Na 2 CO 3. The effects of various factors, including concentration of simulated seawater concentrate, current density, CO 2 aeration rate, and circulating flow rate of alkali chamber, on the quality of Na 2 CO 3 product, carbon sequestration rate, and energy consumption were investigated. Under the optimal condition, the CO 3 2– concentration in the alkaline chamber reached a maximum of 0.817 mol/L with 98 mol% purity. The resulting carbon fixation rate was 70.50%, with energy consumption for carbon sequestration and product production of 5.7 kWhr/m3 CO 2 and 1237.8 kWhr/ton Na 2 CO 3 , respectively. This coupling design provides a triple-win outcome promoting waste reduction and efficient utilization of resources. [Display omitted] [ABSTRACT FROM AUTHOR]

Aminoacetaldehyde (glycinal, NH2CH2CHO) is a first-generation oxidation product of monoethanolamine (MEA, NH2CH2CH2OH), a solvent widely used for CO2 gas separation, which is proposed as the basis for a range of carbon capture technologies. A complete oxidation mechanism for MEA is required to understand the atmospheric transformation of carbon capture plant emissions, as well as the degradation of this solvent during its use and the oxidative destruction of waste solvent. In this study, we have investigated the •OH radical-initiated oxidation chemistry of aminoacetaldehyde using quantum chemical calculations and RRKM theory/master equation kinetic modeling. This work predicts that aminoacetaldehyde has a tropospheric lifetime of around 6 h and that the reaction predominantly produces the NH2CH2C•O radical intermediate at room temperature, along with minor contributions from NH2•CHCHO and •NHCH2CHO. The dominant radical intermediate NH2CH2C•O is predicted to promptly dissociate to NH2•CH2 and CO, where NH2•CH2 is known to react with O2 under tropospheric conditions to form the imine NH = CH2 + HO2. The NH2•CHCHO radical experiences captodative stabilization and is found to form a weakly bound peroxyl radical upon reaction with O2. Instead, the major oxidation product of NH2•CHCHO and the aminyl radical •NHCH2CHO is the imine NH = CHCHO (+HO2). In the atmosphere, the dominant fate of imine compounds is thought to be hydrolysis, where NH = CH2 will form ammonia and formaldehyde, and NH = CHCHO will produce ammonia and glyoxal. Efficient conversion of the dominant first-generation oxidation products of MEA to ammonia is consistent with field observations and supports the important role of imine intermediates in MEA oxidation. [ABSTRACT FROM AUTHOR]

The rising negative effects of climate change are caused mainly by the increase of atmospheric carbon dioxide concentrations, calling for advanced technologies to extract carbon dioxide from atmospheric air. Here we review carbon dioxide capture from atmospheric air by amine-functionalized silica composites with emphasis on development principles, mechanisms, absorbent criteria, performance determination, and preparation techniques. Amine-silica absorbent preparation for carbon dioxide capture is done by impregnation, chemical graphting, hybrid functionalization, and in situ polymerization. High costs, poor performance, and scalability are actually posing challenges for large-scale deployment. [ABSTRACT FROM AUTHOR]

Industrial thin-film composite (TFC) membranes achieve superior gas separation properties from high-performance selective layer materials, while the success of membrane technology relies on high-performance gutter layers to achieve production scalability and low-cost manufacturing. However, the current literature predominantly focuses on the design of polymer architectures to obtain high permeability and selectivity, while the art of fabricating gutter layers is usually safeguarded by industrial manufacturers and appears lackluster to academic researchers. This is the first report aiming to provide a comprehensive and critical review of state-of-the-art gutter layer materials and their design and modification to enable TFC membranes with superior separation performance. We first elucidate the importance of the gutter layer on membrane performance through modeling and experimental results. Then various gutter layer materials used to obtain high-performance composite membranes are critically reviewed, and the strategies to improve their compatibility with the selective layer are highlighted, such as oxygen plasma treatment, polydopamine deposition, and surface grafting. Finally, we present the opportunities of the gutter layer design for practical applications. [ABSTRACT FROM AUTHOR]

This review critically evaluates the algal–bacterial consortium (ABC) as a promising technology for wastewater treatment, carbon capture and storage, while also assessing its challenges and opportunities. The ABC system, characterized by the coupling of algae and bacteria, not only removes pollutants and reclaims resources but also helps in reducing greenhouse gas emissions. This system harnesses algal photosynthesis and bacterial degradation of organic matters to establish a carbon cycle, enhancing biomass production and pollutant removal. Despite its promise, the ABC process is subject to several hurdles, including sensitivity to low temperatures, reliance on artificial illumination, and the potential for algal biomass contamination by toxic substances. To capitalize on its full potential, continued research and technological advancements are imperative. Future investigations should focus on optimizing the system's operational efficiency, developing precise process models, exploring avenues for resource recovery, and broadening the scope of its applications. By surmounting these challenges, the ABC system has the capacity to make a significant impact on sustainable wastewater management and carbon fixation. [ABSTRACT FROM AUTHOR]

The anaerobic digestion of aqueous condensate from fast pyrolysis is a promising technology for enhancing carbon and energy recovery from waste. Syngas, another pyrolysis product, could be integrated as a co-substrate to improve process efficiency. However, limited knowledge exists on the co-fermentation of pyrolysis syngas and aqueous condensate by anaerobic cultures and the effects of substrate toxicity. This work investigates the ability of mesophilic and thermophilic anaerobic mixed cultures to co-ferment syngas and the aqueous condensate from either sewage sludge or polyethylene plastics pyrolysis in semi-batch bottle fermentations. It identifies inhibitory concentrations for carboxydotrophic and methanogenic reactions, examines specific component removal and assesses energy recovery potential. The results show successful co-fermentation of syngas and aqueous condensate components like phenols and N-heterocycles. However, the characteristics and load of the aqueous condensates affected process performance and product formation. The toxicity, likely resulting from the synergistic effect of multiple toxicants, depended on the PACs' composition. At 37 °C, concentrations of 15.6 gCOD/gVSS and 7.8 gCOD/gVSS of sewage sludge-derived aqueous condensate inhibited by 50% carboxydotrophic and methanogenic activity, respectively. At 55 °C, loads between 3.9 and 6.8 gCOD/gVSS inhibited by 50% both reactions. Polyethylene plastics condensate showed higher toxicity, with 2.8 gCOD/gVSS and 0.3 gCOD/gVSS at 37 °C decreasing carboxydotrophic and methanogenic rates by 50%. At 55 °C, 0.3 gCOD/gVSS inhibited by 50% CO uptake rates and methanogenesis. Increasing PAC loads reduced methane production and promoted short-chain carboxylates formation. The recalcitrant components in sewage sludge condensate hindered e-mol recovery, while plastics condensate showed high e-mol recoveries despite the stronger toxicity. Even with challenges posed by substrate toxicity and composition variations, the successful conversion of syngas and aqueous condensates highlights the potential of this technology in advancing carbon and energy recovery from anthropogenic waste streams. [ABSTRACT FROM AUTHOR]

There has been a growing recognition in recent years that Electrofuels (e-fuels), also known as renewable and sustainable fuels, which are produced from hydrogen and carbon dioxide as the primary feedstocks, have great potential to reduce carbon footprint and address climate change. In the present study, contrary to most previous studies in which the sources of feedstock's preparation were considered as block boxes, two stand-alone processes are taken into account and incorporated into the e-fuels production system. H 2 is obtained by a high-temperature electrolysis system having an overall efficiency nearly twice that of a low-temperature electrolysis system. CO 2 is captured from a power plant flue gas stream with a purity of 99.81%. Investigating heat integration potential in such an integrated plant is an up-to-date and interesting topic and has not yet been well explored. Therefore, a heat integration within the three individual processes is implemented to reduce energy consumption. The design of the process-to-process heat transfer section is carried out using pinch design rules. By integrating individual units, approximately 42% of the required cold utility, traditionally supplied by chilled water and refrigerants, is allocated to generate high and medium-pressure steams. Having used the high-temperature steam electrolysis for H 2 production, a process that requires less external electricity compared to low-temperature water electrolysis, a power-to-liquid efficiency of 70% is achieved. Furthermore, the results reveal a carbon conversion ratio of 98.6%, indicating the effective converting the carbon from the feedstock into liquid hydrocarbons. [Display omitted] • Heat integration between e-fuels unit and its feedstocks supplier units is done. • Shell-and-tube and plate-fin exchangers are used to design heat exchanger network. • Required cold utilities in the processes decreases by 42% by steam generation. • Power-to-liquid efficiency is improved by 70% through the integration. • Effective converting carbon from the feedstock into liquid hydrocarbons by 98.62%. [ABSTRACT FROM AUTHOR]

Biorenewable hydrogen is requisite to replace non-renewable hydrogen. Decarbonization is assured. Hydrogen demand is severely rising due to mitigating climate change and reducing fossil fuel dependency. Green Hydrogen from agro waste proposition makes bio-circular economy upcycling. The main objective of this study is to reinforce the hope of renewable, sustainable H 2 production from agro-waste. Initially, this paper shows the demand for green hydrogen, the sustainable availability of agro waste, and their capability to produce H 2. Insights into the gasification of agro waste about cellulose, hemicellulose, and lignin with conventional gasification. The effect of catalyst and supercritical gasification and their challenges is discussed. Most uniquely, other reviews highlight various aspirations behind agro-waste gasification to attain a strong business model, such as co-production, co-gasification, and CO 2 reforming with H2 yield. This review exhibits some main insight into various aspects of agro-waste gasification. H 2 from agrowaste gasification has high energy content (122 kJ/g) and high energy conversion efficiency in the range of 55–58 %, in addition to gaining the economic penalties of 2.2–2.5 net points for decarbonization. Agro waste is composed of lignocellulosic material that is relatively richer in hydrogen than fossil fuel resources. In SCWG, water is one of the natural solvents, which means feedstock effectively dissolves with water solvents. Intermittent density, low viscosity, and surface tension are nearly zero values due to SCW having no specific phase boundary, which enhances the gasification and substantially reduces tar formation during SCWG. Catalyst utilization enhances H 2 production. The present study comprehensively exhibits the role of catalyst and their supporter and promoter. Ni-based catalysts are mostly suggested for H2 production but fall into reusability issues. The main reason behind this is that Ni is inefficient in removing HCl, H 2 S, and total trace elements during gasification. Recently, low-cost and waste-to-wealth transformation aspects of biochar-based catalysts have gained attention. Renewable-assisted gasification significantly improves the energy and exergy of the system and suppresses the important concern of energy consumption during gasification. Renewable assisted and various aspiration incorporation into gasification is solidly recommended for future implementation based on energy, economic, and environmental benefits from them. Plastic and biomass are richer in hydrocarbon and oxygen, respectively; this synergistic effect has the potential to enhance the H 2 yield. From this study, PP plastic is mostly preferred for co-gasification with biomass. Compared to 100 wt% of biomass, the introduction of plastic slightly increased the coke formation, but the H 2 yield was improved. When the plastic mixture of 10 wt% increases coke deposition, however, significant coke deposition is not reported when 20 wt% of plastic concentration is not reported. Carbon capture via CO 2 inert gas supply enhances the H 2 yield, provides a route to carbon trade, and substantially contributes to GHG pollution mitigation. Agro-waste gasification is produced by a product that has the potential to be used in a wide range of applications due to its unique properties, such as large specific surface area, porosity, functional groups, high reliability, and minimum cost. Hopefully, this review will be an optic to the most appropriate green hydrogen production path for sustainable clean energy production and effective agro-waste management. • This review acts as an optic to the most appropriate green hydrogen production path. • Hydrogen separation, purification, and storage need more care. • Carbon dioxide reformation aids a carbon trading system and reduces environmental effect. • These research provide direction for energy nexuses that may be derived from agricultural waste. [ABSTRACT FROM AUTHOR]

CO2 mineralization products are often heralded as having outstanding potentials to reduce CO2-eq. emissions. However, these claims are generally undermined by incomplete consideration of the life cycle climate change impacts, material properties, supply and demand constraints, and economic viability of CO2 mineralization products. We investigate these factors in detail for ten concrete-related CO2 mineralization products to quantify their individual and global CO2-eq. emissions reduction potentials. Our results show that in 2020, 3.9 Gt of carbonatable solid materials were generated globally, with the dominant material being end-of-life cement paste in concrete and mortar (1.4 Gt y-1). All ten of the CO2 mineralization technologies investigated here reduce life cycle CO2-eq. emissions when used to substitute comparable conventional products. In 2020, the global CO2-eq. emissions reduction potential of economically competitive CO2 mineralization technologies was 0.39 Gt CO2-eq., i.e., 15% of that from cement production. This level of CO2-eq. emissions reduction is limited by the supply of end-of-life cement paste. The results also show that it is 2 to 5 times cheaper to reduce CO2-eq. emissions by producing cement from carbonated end-of-life cement paste than carbon capture and storage (CCS), demonstrating its superior decarbonization potential. On the other hand, it is currently much more expensive to reduce CO2-eq. emissions using some CO2 mineralization technologies, like carbonated normal weight aggregate production, than CCS. Technologies and policies that increase recovery of end-of-life cement paste from aged infrastructure are key to unlocking the potential of CO2 mineralization in reducing the CO2-eq. footprint of concrete materials. [ABSTRACT FROM AUTHOR]

Using carbon-based materials (CBMs) to facilitate phytoremediation shows great promise for simultaneously enhancing the restoration efficiency of contaminated soil and reducing carbon dioxide in the context of global warming, which is still in the exploring and attempting phase. In addition to direct degradation or alteration of pollutant bioavailability, CBMs can enhance phytoremediation by alleviating plant nutrient deprivation and oxidative stress, as well as by modulating soil microbial communities and root secretions. Photosynthetic carbon fixation predominantly affects both phytoremediation efficiency and carbon cycle turnover in terrestrial ecosystems. In this regard, CBMs have extremely positive properties in facilitating plant carbon capture, with intrinsic mechanisms including (1) promoting photosynthetic pigment synthesis and acting as artificial built-in antennae to improve photon capture efficiency, (2) accelerating the photosynthetic electron transport rate in photosystems, (3) improving the Calvin cycle, and (4) maintaining the structural integrity of chloroplasts. Besides, as an ultra-stable type of CBM derived from waste biomass, biochar can preserve the native biomass carbon in the soil environment for decades and attenuate the rhizosphere priming effect by influencing the structure of rhizosphere soil aggregates and microbial communities, thus retarding the native soil organic carbon efflux. This review critically elaborates on the mechanisms by which CBMs assist in improving the efficiency of phytoremediation and their positive effects on the plant-root soil carbon balance. Additionally, a simple full-life cycle analysis encompassing cost analysis as well as ecological, economic, and social benefits is concluded to evaluate the feasibility and sustainability of CBMs-phytoremediation systems. [ABSTRACT FROM AUTHOR]

This study investigates the synthesize of activated carbon for carbon dioxide adsorption using palm kernel shell (PKS), a by-product of oil palm industry. The adsorbent synthesis involved a simple two-step carbonization method. Firstly, PKS was activated with potassium oxide (KOH), followed by functionalization with magnesium oxide (MgO). Surface analysis revealed that KOH activated PKS has resulted in a high specific surface area of 1086 m2/g compared to untreated PKS (435 m2/g). However, impregnation of MgO resulted in the reduction of surface area due to blockage of pores by MgO. Thermogravimetric analysis (TGA) demonstrated that PKS-based adsorbents exhibited minimal weight loss of less than 30% up to 500 °C, indicating their suitability for high-temperature applications. CO2 adsorption experiments revealed that PKS-AC-MgO has achieved a higher adsorption capacity of 155.35 mg/g compared to PKS-AC (149.63 mg/g) at 25 °C and 5 bars. The adsorption behaviour of PKS-AC-MgO was well fitted by both the Sips and Langmuir isotherms, suggesting a combination of both heterogeneous and homogeneous adsorption and indicating a chemical reaction between MgO and CO2. Thermodynamic analysis indicated a spontaneous and thermodynamically favourable process for CO2 capture by PKS-AC-MgO, with negative change in enthalpy (− 0.21 kJ/mol), positive change in entropy (2.44 kJ/mol), and negative change in Gibbs free energy (− 729.61 J/mol, − 790.79 J/mol, and − 851.98 J/mol) across tested temperature. Economic assessment revealed that the cost of PKS-AC-MgO is 21% lower than the current market price of commercial activated carbon, indicating its potential for industrial application. Environmental assessment shows a significant reduction in greenhouse gas emissions (381.9 tCO2) through the utilization of PKS-AC-MgO, underscoring its environmental benefits. In summary, the use of activated carbon produced from PKS and functionalised with MgO shows great potential for absorbing CO2. This aligns with the ideas of a circular economy and sustainable development. [ABSTRACT FROM AUTHOR]

Although methane poses environmental concerns, it is employed in hydrogen production processes such as steam‐methane reforming (SMR), which has an issue of by‐products released. Initiatives are being pursued to address CO and CO2 emissions using carbon capture methods, with the goal of minimizing environmental harm while improving pure hydrogen generation from syngas. In this study, porous coordination network (PCN‐250) has been studied for its selective adsorption property towards CO, CO2 and H2O as syngas mixture to obtain pure hydrogen. For this purpose, the trimetallic cluster node Fe2M (where Fe2 represents the 3+ oxidation state and M is Cr(II), Mn(II), Fe(II), Co(II), Ni(II), and Zn(II)) has been considered. Fe(III) in combination with metal atoms like Cr(II), Co(II), or Ni(II) has been found to exhibit enhanced adsorption properties towards CO, CO2 and H2O. The molecule with the strongest interaction was found to be H2O over Fe(III)2Zn(II) cluster and weakest interaction was found between H2 and Fe(III)2Ni(II). Charge transfer, natural bond orbital (NBO) and spin density analyses reveal the electronic structural properties of this combination, leading to enhanced adsorption of CO and CO2. [ABSTRACT FROM AUTHOR]

Globally, the release of greenhouse gases primarily carbon dioxide (CO2) emissions to our Earth's surface has climbed by about 45% to its present atmospheric concentration rate of 420 parts per million (ppm) during the industrial era. An unprecedented rise in atmospheric CO2 concentration has been claimed to lead to significant factors such as global warming potential (GWP) and climate change effects. An increase in atmospheric CO2 concentrations is a serious threat to the environment. Recent research efforts have focused on mitigating emissions from anthropogenic point sources. Adsorption-based post-combustion CO2 capture using solid adsorbents is the most effective and efficient method for mitigating gas adsorption in the exhaust system. In the current study, activated carbons are obtained from three potential biomass, namely, (i) coconut shell, (ii) rice husk, and (iii) eucalyptus wood, through a - single-stage activation method. The prepared activated carbon materials are analyzed using proximate and ultimate analyses. Further investigations are performed using different characterization techniques to ensure their adsorption efficiency. Adsorbents are packed one after the other in an in-house fabricated double adsorption chamber and coupled to the exhaust unit of a generator. Test experiments are conducted to examine adsorbents' capture efficiency in emissions mitigation. Adsorbents' adsorption parameters are evaluated in experimental investigations. At 2.5 bar and 50 °C, a maximum loading capacity of samples is achieved by 4.85 mmol/g, 4.58 mmol/g, and 5.96 mmol/g for coconut shell, rice husk, and eucalyptus wood adsorbents, respectively. With a post-combustion carbon adsorption chamber, CO2 and NO are captured about 40–64% and 38–58%, respectively, for all three adsorbents. The thermodynamic parameter of isosteric heat of adsorption value is below 40 kJ/mol, ensuring physisorption for all adsorbents. [ABSTRACT FROM AUTHOR]

The technical and economic challenges are enormous in developing gas wells with a high CO2 content (> 50 mol %), such as the East Natuna gas field, which has 71 mol % (86 mass %). Carbon capture technology in gas wells with high CO2 content is studied to find a more economical one. In this study, the technology for capturing high concentrations of CO2 is varied from gas wells, Controlled Freeze Zone (CFZ), and cryogenic distillation which will be analyzed based on cost. Variations in the CO2 content of gas wells are 75 %, 80 %, 85 %, 90 %, and 95 % in mass fraction simulated using Aspen Plus V.11.0. Based on this research, CFZ technology and cryogenic distillation can obtain purity up to 99 % and recovery above 78 %. However, the total annual cost (annual capital and operating costs) of CFZ technology is lower than cryogenic distillation technology, so CFZ technology is suitable for capturing CO2 in gas wells with high CO2 content. [ABSTRACT FROM AUTHOR]

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Industrial emissions are significant and need to be addressed in the fight against climate change. To achieve carbon emission reduction targets in line with climate change policies while maintaining the competitiveness of the industry, hard-to-abate sectors are exploring efficient carbon reduction technologies and striving to reduce associated costs. Carbon capture technology presents a large-scale CO2 reduction solution with immense potential. In promoting the application of carbon capture in hard-to-abate industries, it is essential to comprehensively analyze the feasibility and economics of carbon capture technology. This paper conducts a review of the technical feasibility and economics of carbon capture technologies in several industrial sectors, namely iron and steel, cement, and coal chemical industries. A vast amount of data on the costs of industrial carbon capture technologies has been gathered for comparison. This study also specifically addresses policy incentives that have been discussed and are currently being implemented to cut costs and promote industrial carbon capture projects. [ABSTRACT FROM AUTHOR]

This study reviews the steps Canada is taking to address sustainable decarbonization in the context of carbon capture. This work also presents a new optimal framework for national optimal deployment in need of strategic carbon capture implementation. This framework considers external environmental and social considerations often missing from implementation frameworks, which will aid policy makers in more well‐rounded deployment decisions. Thus far, Canada's carbon projects have captured a total of 36.3 Mt of CO2 which has cost over $2.7 billion to implement. The Canadian case study utilizing the proposed optimal planning strategy shows that implementation of 58 post‐combustion carbon capture (PCC) plants located in seven provinces (Alberta, British Columbia, New Brunswick, Nova Scotia, Ontario, Quebec, and Saskatchewan) would result in Canada meeting the national targets. This implementation includes 16 plants removing emissions from the Electricity sector, 16 from the Heavy Industry sector, and 26 from the Oil and gas sector resulting in new emissions levels of 11.82 MtCO2, 27.63 MtCO2, and 107.01 MtCO2 in each sector, respectively. Additional case studies examined the impact of Alberta's emissions and varying the national targets resulting in different optimal implementations plans. Through a sensitivity analysis on these targets, it was determined that plant distribution is heavily dependent on provincial energy and CO2 transport prices. Additionally, if Alberta were to reduce their GHG emissions by 50% through alternative sustainable methods, only 35 PCC plants would be required to meet national targets. This framework provides a sustainable tool for decision‐makers to accelerate decarbonization. [ABSTRACT FROM AUTHOR]

Lowering the adverse effects of climate change requires advanced methods to decrease atmospheric levels of carbon dioxide. Here, we review the use of carbonic anhydrase nanobiocatalysts for carbon dioxide sequestration, with emphasis on inorganic, organic, and polymeric nanomaterials. Inorganic nanomaterials include metal and metal oxide, carbon-based, and nonmetallic nanomaterials. Hybrid nanomaterials comprise metal–organic frameworks and nanoflowers. Factors influencing the properties of nanobiocatalysts such as interactions between carbonic anhydrase and the nanoscale support are presented. The immobilization of carbonic anhydrase onto nanomaterials overcomes the limitations associated with its free form, such as short shelf life, challenging separation, and poor reusability. We discuss the potential for large-scale applications. [ABSTRACT FROM AUTHOR]

In approximately one decade, global temperatures will likely exceed a warming level that a United Nations Intergovernmental Panel on Climate Change report considers a "red alert for humanity". We propose exploring tidal flat diatoms to address climate change challenges. Tidal flats are extensive coastal ecosystems crucial to the provisioning and regulation of aquatic environments. Diatoms contribute to tidal flat biomass production and account for 20% of global primary productivity and 40% of annual marine biomass production, making them crucial for nutrient cycling and sediment stabilization. Potential CO2 removal from Korean tidal flats by diatoms is estimated to be 598,457–683,171 t CO2 equivalents (CO2e) annually, with the economic value of blue carbon (BC) resulting from diatom activity being approximately US$ 17.95–20.50 million. Dissemination of this potential could incentivize coastal wetland protection and climate change mitigation measures. The global estimated CO2e removal potential of tidal flat diatoms is 40,957,346–46,754,961 t CO2e, representing 0.11–0.13% of the annual global greenhouse gas emissions, even though tidal flats cover 0.0025% of the Earth's surface and diatoms represent less than 0.5% (by weight) of all photosynthetic plants. Researchers should combine ecology and economics to develop standardized approaches for carbon input monitoring and quantification. Further, spatiotemporal analyses of environmental threats to tidal flat diatoms are necessary for conserving their biodiversity and function as a critical BC source. Land-based cultivation for large-scale biomass production and biorefinery processes can contribute to a greener, more prosperous future for humanity and the marine ecosystems upon which we rely. [ABSTRACT FROM AUTHOR]

Abstract Hybrid thermochemical–biological processes have the potential to enhance the carbon and energy recovery from organic waste. This work aimed to assess the carbon and energy recovery potential of multifunctional processes to simultaneously sequestrate syngas and detoxify pyrolysis aqueous condensate (PAC) for short-chain carboxylates production. To evaluate relevant process parameters for mixed culture co-fermentation of syngas and PAC, two identical reactors were run under mesophilic (37 °C) and thermophilic (55 °C) conditions at increasing PAC loading rates. Both the mesophilic and the thermophilic process recovered at least 50% of the energy in syngas and PAC into short-chain carboxylates. During the mesophilic syngas and PAC co-fermentation, methanogenesis was completely inhibited while acetate, ethanol and butyrate were the primary metabolites. Over 90% of the amplicon sequencing variants based on 16S rRNA were assigned to Clostridium sensu stricto 12. During the thermophilic process, on the other hand, Symbiobacteriales, Syntrophaceticus, Thermoanaerobacterium, Methanothermobacter and Methanosarcina likely played crucial roles in aromatics degradation and methanogenesis, respectively, while Moorella thermoacetica and Methanothermobacter marburgensis were the predominant carboxydotrophs in the thermophilic process. High biomass concentrations were necessary to maintain stable process operations at high PAC loads. In a second-stage reactor, Aspergillus oryzae converted acetate, propionate and butyrate from the first stage into L-malate, confirming the successful detoxification of PAC below inhibitory levels. The highest L-malate yield was 0.26 ± 2.2 molL-malate/molcarboxylates recorded for effluent from the mesophilic process at a PAC load of 4% v/v. The results highlight the potential of multifunctional reactors where anaerobic mixed cultures perform simultaneously diverse process roles, such as carbon fixation, wastewater detoxification and carboxylates intermediate production. The recovered energy in the form of intermediate carboxylates allows for their use as substrates in subsequent fermentative stages.

Mineral carbonation is emerging as a reliable CO2 capture technology that can mitigate climate change. In lime-treated clayey soils, mineral carbonation occurs through the carbonation of free lime and cementitious products derived from pozzolanic reactions. The kinetics of the reactions in lime-treated clayey soils are variable and depend primarily on soil mineralogy. The present study demonstrates the role of soil mineralogy in CO2 capture and the subsequent changes caused by carbon mineralization in terms of the unconfined compressive strength (UCS) of lime-treated soils during their service life. Three clayey soils (kaolin, bentonite, and silty clay) with different mineralogical characteristics were treated with 4% lime content, and the samples were cured in a controlled environment for 7 d, 90 d, 180 d, and 365 d. After the specified curing periods, the samples were exposed to CO2 in a carbonation cell for 7 d. The non-carbonated samples purged with N2 gas were used as a benchmark to compare the mechanical, chemical-mineralogical, and microstructure changes caused by carbonation reactions. Experimental investigations indicated that exposure to CO2 resulted in an average increase of 10% in the UCS of lime-treated bentonite, whereas the strength of lime-treated kaolin and silty clay was reduced by an average of 35%. The chemical and microstructural analyses revealed that the precipitated carbonates effectively filled the macropores of the treated bentonite, compared to the inadequate cementation caused by pozzolanic reactions, resulting in strength enhancement. In contrast, strength loss in lime-treated kaolin and silty clay was attributed to the carbonation of cementitious phases and partly to the tensile stress induced by carbonate precipitation. In terms of carbon mineralization prospects, lime-treated kaolin exhibited maximum carbonation due to the higher availability of unreacted lime. The results suggest that, in addition to the increase in compressive strength, adequate calcium-bearing phases and macropores determine the efficiency of carbon mineralization in lime-treated clayey soils.

The construction scale of a wastewater centralized treatment facility in a printing and dyeing cluster improvement park in Zhejiang Province was 30 000 m3/d. According to the characteristics of wastewater in the park, the main process of “regulation tank+cooling system+reaction initial sedimentation tank+anaerobic hydrolysis tank+A/O biochemical tank+secondary sedimentation tank+high-efficiency sedimentation tank” was adopted. The results showed that the process was stable and efficient. When the average COD, BOD5, and total antimony in the influent were 1 370, 360 and 1.17 mg/L, the COD, BOD5, and total antimony in effluent were respectively reduced to 88, 7.4, and 0.049 mg/L, with the corresponding removal rates of 94%, 98% and 96%. The effluent met the indirect discharge requirements in Table 2 of “Discharge Standards of Water Pollutants for Dyeing and Finishing of Textile Industry”(GB 4287-2012). The project adopted a coagulation agent enhanced initial sedimentation process to achieve effective carbon capture of wastewater and indirectly export energy, which was conducive to the reduction of carbon emissions. The main treatment unit adopted intensive combination and deep pool design to save land, which could be used as a reference for land limited wastewater plants.

Abstract Background Microbially induced calcium carbonate precipitation has been extensively researched for geoengineering applications as well as diverse uses within the built environment. Bacteria play a crucial role in producing calcium carbonate minerals, via enzymes including carbonic anhydrase—an enzyme with the capability to hydrolyse CO2, commonly employed in carbon capture systems. This study describes previously uncharacterised carbonic anhydrase enzyme sequences capable of sequestering CO2 and subsequentially generating CaCO3 biominerals and suggests a route to produce carbon negative cementitious materials for the construction industry. Results Here, Bacillus subtilis was engineered to recombinantly express previously uncharacterised carbonic anhydrase enzymes from Bacillus megaterium and used as a whole cell catalyst allowing this novel bacterium to sequester CO2 and convert it to calcium carbonate. A significant decrease in CO2 was observed from 3800 PPM to 820 PPM upon induction of carbonic anhydrase and minerals recovered from these experiments were identified as calcite and vaterite using X-ray diffraction. Further experiments mixed the use of this enzyme (as a cell free extract) with Sporosarcina pasteurii to increase mineral production whilst maintaining a comparable level of CO2 sequestration. Conclusion Recombinantly produced carbonic anhydrase successfully sequestered CO2 and converted it into calcium carbonate minerals using an engineered microbial system. Through this approach, a process to manufacture cementitious materials with carbon sequestration ability could be developed.

Biogenic volatile organic compounds (BVOCs) are responsible for the formation of ozone and secondary organic aerosols (SOAs). Our knowledge about how black carbon particles influence BVOC emissions from terrestrial ecosystems is limited; terrestrial vegetation captures black carbon particles as a sink. In this research, the BVOC emissions from the leaves of four terrestrial plants were measured using an RAE PGM-7300 BVOC analyzer. Then, the leaves from four types of trees were exposed to submicron carbon black for 24 h and 48 h in an ambient environment, respectively. Comparisons between the BVOC emissions before and after exposure to submicron carbon black were performed. Our results indicated that the emissions of BVOC from the leaves of four types of trees varied from 90 to 270 μg g−1 h−1 and depended on the species. The exposure to submicron black carbon particles had negligible impacts on the BVOC emissions from the leaves of four types of trees.

Abstract In the pursuit of unconventional binders that can reduce energy consumption in production, magnesium oxysulfate (MOS) cement emerges as a viable alternative. Moreover, carbon dioxide (CO2) has been employed in the curing process of certain MOS cement products, such as magnesia fiber cement, due to its capacity to enhance their performance. This study aims to assess the impact of pre-curing prior to accelerated carbonation on the physical-mechanical properties of magnesium oxide fiber cement boards. These boards were manufactured using the Hatschek process simulation and subjected to pre-curing periods of 24, 48, and 72 h post-production. The relationship between microstructural alterations and the physical-mechanical properties was examined through analyses including water absorption, apparent porosity, apparent density, four-point bending tests, X-ray diffraction, and scanning electron microscopy analyses. The results indicated that pre-curing had an influence on the physical-mechanical attributes of the manufactured boards. After 72 h, the carbonated materials exhibited a decline in mechanical performance, a phenomenon attributed to the carbonation reactions between CO2 and the hydration products responsible for enhancing the mechanical strength of the cementitious materials.

Direct Air Capture (DAC) offers a promising pathway for combating climate change by removing carbon dioxide (CO2) directly from the atmosphere. Here, we discuss Heirloom's approach to DAC, which uses naturally occurring minerals, namely, calcium carbonate (CaCO3), in a cyclic process that leverages warehouse automation systems previously developed for large warehouses. The integration of DAC with warehouse automation systems unlocks a degree of manufacturability, scalability, operational efficiency, and financial viability. For successful scaling, DAC technologies and project developers must think through key scalability constraints, including modularity, constructability, supply chains, and leveraging existing infrastructure. [ABSTRACT FROM AUTHOR]

Hybrid thermochemical–biological processes have the potential to enhance the carbon and energy recovery from organic waste. This work aimed to assess the carbon and energy recovery potential of multifunctional processes to simultaneously sequestrate syngas and detoxify pyrolysis aqueous condensate (PAC) for short-chain carboxylates production. To evaluate relevant process parameters for mixed culture co-fermentation of syngas and PAC, two identical reactors were run under mesophilic (37 °C) and thermophilic (55 °C) conditions at increasing PAC loading rates. Both the mesophilic and the thermophilic process recovered at least 50% of the energy in syngas and PAC into short-chain carboxylates. During the mesophilic syngas and PAC co-fermentation, methanogenesis was completely inhibited while acetate, ethanol and butyrate were the primary metabolites. Over 90% of the amplicon sequencing variants based on 16S rRNA were assigned to Clostridium sensu stricto 12. During the thermophilic process, on the other hand, Symbiobacteriales, Syntrophaceticus, Thermoanaerobacterium, Methanothermobacter and Methanosarcina likely played crucial roles in aromatics degradation and methanogenesis, respectively, while Moorella thermoacetica and Methanothermobacter marburgensis were the predominant carboxydotrophs in the thermophilic process. High biomass concentrations were necessary to maintain stable process operations at high PAC loads. In a second-stage reactor, Aspergillus oryzae converted acetate, propionate and butyrate from the first stage into L-malate, confirming the successful detoxification of PAC below inhibitory levels. The highest L-malate yield was 0.26 ± 2.2 molL-malate/molcarboxylates recorded for effluent from the mesophilic process at a PAC load of 4% v/v. The results highlight the potential of multifunctional reactors where anaerobic mixed cultures perform simultaneously diverse process roles, such as carbon fixation, wastewater detoxification and carboxylates intermediate production. The recovered energy in the form of intermediate carboxylates allows for their use as substrates in subsequent fermentative stages. [ABSTRACT FROM AUTHOR]

Even though the energy penalties and solvent regeneration costs associated with amine-based absorption/stripping systems are important challenges, this technology remains highly recommended for post-combustion decarbonization systems given its proven capture efficacy and technical maturity. This study introduces a novel centralized and decentralized hybrid control strategy for the post-combustion carbon capture plant, aimed at mitigating main disturbances and sustaining high system performance. The strategy is rooted in a comprehensive mathematical model encompassing absorption and desorption columns, heat exchangers and a buffer tank, ensuring smooth operation and energy efficiency. The buffer tank is equipped with three control loops to finely regulate absorber inlet solvent solution parameters, preventing disturbance recirculation from the desorber. Additionally, a model-based controller, utilizing the model predictive control (MPC) algorithm, maintains a carbon capture yield of 90% and stabilizes the reboiler liquid temperature at 394.5 K by manipulating the influent flue gas to the lean solvent flowrates ratio and the heat duty of the reboiler. The hybrid MPC approach reveals efficiency in simultaneously managing targeted variables and handling complex input–output interactions. It consistently maintains the controlled variables at desired setpoints despite CO2 flue gas flow disturbances, achieving reduced settling time and low overshoot results. The hybrid control strategy, benefitting from the constraint handling ability of MPC, succeeds in keeping the carbon capture yield above the preset minimum value of 86% at all times, while the energy performance index remains below the favorable value of 3.1 MJ/kgCO2. [ABSTRACT FROM AUTHOR]

Background: Microbially induced calcium carbonate precipitation has been extensively researched for geoengineering applications as well as diverse uses within the built environment. Bacteria play a crucial role in producing calcium carbonate minerals, via enzymes including carbonic anhydrase—an enzyme with the capability to hydrolyse CO2, commonly employed in carbon capture systems. This study describes previously uncharacterised carbonic anhydrase enzyme sequences capable of sequestering CO2 and subsequentially generating CaCO3 biominerals and suggests a route to produce carbon negative cementitious materials for the construction industry. Results: Here, Bacillus subtilis was engineered to recombinantly express previously uncharacterised carbonic anhydrase enzymes from Bacillus megaterium and used as a whole cell catalyst allowing this novel bacterium to sequester CO2 and convert it to calcium carbonate. A significant decrease in CO2 was observed from 3800 PPM to 820 PPM upon induction of carbonic anhydrase and minerals recovered from these experiments were identified as calcite and vaterite using X-ray diffraction. Further experiments mixed the use of this enzyme (as a cell free extract) with Sporosarcina pasteurii to increase mineral production whilst maintaining a comparable level of CO2 sequestration. Conclusion: Recombinantly produced carbonic anhydrase successfully sequestered CO2 and converted it into calcium carbonate minerals using an engineered microbial system. Through this approach, a process to manufacture cementitious materials with carbon sequestration ability could be developed. [ABSTRACT FROM AUTHOR]

A new strategy for ultramicroporous activated carbons production from avocado seeds was developed. Combined solvothermal carbonization and thermal KOH activation were conducted. Solvothermal carbonizations were performed in a stainless-steel autoclave lined with Teflon at the temperature of 180 °C for 12 h in three different liquids (water, methanol, isopropyl alcohol). Chars were activated by KOH. The carbonization combined with activation took place in the oven at 850 °C for 1 h. All the samples were very good CO2 sorbents. The highest CO2 adsorption at a pressure of 1 bar was achieved for activated carbon produced using isopropanol. The best carbon dioxide adsorption was equal to 6.47 mmol/g at 0 °C and 4.35 mmol/g at 20 °C. [ABSTRACT FROM AUTHOR]

Livestock production is one of the most important agricultural sources of greenhouses gasses (GHG). Transforming the livestock sector is a critical task to mitigate the effects of climate change, and the implementation of silvopastoral systems (SPS) may be a way to do so. Carbon footprint (CF) estimation was carried out for 131 conventional livestock farms (CONF) and SPS farms (SPSF) selected in the states of Jalisco, Chiapas and Campeche (Mexico). GHG emissions were estimated based on interviews with the farmers and farm monitoring to collect information about management, milk production and the live weight gain (LWG) of calves (for meat production) using national emission factors. Emissions from animals, fossil fuels, electricity and nitrogen fertilizers were estimated using Tier I and II criteria. Land use distribution was recorded for each farm, and their carbon fixation in total biomass and soils was estimated using studies from tropical Latin America. CF was estimated for area and for production of milk and the LWG of calves. SPSF had lower GHG emissions, higher carbon fixation rates and a better CF than CONF (5.7 vs. 8.0 t CO2e/ha/year; 6.9 vs. 5.5 t C/ha/year and - 5.0 vs. -2.9 t CO2e/ha/year, respectively). The CF of milk production and calf LWG were - 68.6 to -4.6 kg CO2e/kg and - 3.2 to -0.1 t CO2e/kg, respectively. Our results highlight the importance of implementing SPS to mitigate climate change in livestock production, given its contribution to GHG emissions and the importance of capturing atmospheric carbon in biomass and soils. National and regional policies should focus on promoting implementing SPS as an active and effective strategy for improving CF in livestock farms. [ABSTRACT FROM AUTHOR]

Solvent-based CO2 capture is a commonly employed post-combustion technique in processes involving absorber-stripper columns. This study focused on computer simulations with equilibrium- and rate-based modeling of CO2 capture using the amine solvents 2-amino-2-methyl-1-propanol (AMP), diethanolamine (DEA), and methyl diethanolamine (MDEA) and thermodynamic methods involving electrolyte NRTL models. The objective of this study was to understand the impacts of rate-based modeling, the type of amine, and thermodynamic methods on carbon capture. Within this study, the amine-based CO2 capture process from coal-power plant flue gas was studied using Aspen Plus modeling. Simulations were also conducted to determine the impact of thermodynamics and kinetics on the CO2 capture performance of the system. The results were analyzed on the basis of captured CO2 according to the solvents and models. The equilibrium approach was mostly invalid because of the oversimplified ideal stage assumptions through the column. The lowest carbon capture capacity was obtained with MDEA, while DEA yielded the best results. A sensitivity analysis with rate-based modeling showed the significant impact of the inlet CO2 composition. The amine-based CO2 capture process simulation included solution chemistry, electrolyte thermodynamics, rigorous transport property modeling, reaction kinetics, and rate-based multistage simulation, which could be applicable to different solvent systems. [ABSTRACT FROM AUTHOR]