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In the face of escalating global climate challenges, effective carbon dioxide (CO₂) capture techniques remain at the forefront of mitigating anthropogenic greenhouse gas emissions. This comprehensive review elucidates the latest advancements in CO₂ capture, emphasizing two predominant methodologies: absorption and adsorption. We delve into the mechanisms underlying each process, highlighting the novel materials and technologies that have emerged over recent years. For absorption, the focus is placed on the material design strategy, and identifying new materials in the class of amines, ionic liquids (ILs) and nanofluids for enhanced CO 2 capture capacities and reduced energy requirements. In the realm of adsorption, the synthesis of innovative adsorbents, such as metal organic framework (MOF), organic polymers, inorganic adsorbents, silicon-based adsorbents, and biochar and byproducts from biomass with superior selectivity and stability, is explored. Additionally, the review addresses the challenges associated with each method, offering insights into potential avenues for further research. By providing a holistic overview of the current landscape of CO₂ capture, this article serves as a pivotal resource for researchers and industry professionals aiming to advance sustainable solutions to combat climate change. [Display omitted] • Absorption and adsorption materials are at the forefront of CO 2 capture technologies. • Ionic-liquids and nanofluids can be comparable to amines with improvements in scalability and stability. • Biomass byproducts as adsorbents offers a sustainable solution to CO 2 capture. [ABSTRACT FROM AUTHOR]

Highlights • LAC GHG efficiency in agricultural sector using within and across country metrics. • 5 Countries offset agriculture emissions with land-use-related carbon sequestration. • Small Caribbean island-states report the worst-case decoupling elasticity scenario. • Top decoupling countries are not equivalent to high factor productivity countries. Abstract The paper explores the relationship between production and greenhouse gas (GHG) emissions in the agricultural sector of Latin America and the Caribbean (LAC) between 1990 and 2015. By appraising how GHG emissions have changed with respect to agricultural production (elasticity), we are able to classify countries into six decoupling states. While the decoupling elasticity provides information for assessing the evolution within countries, we introduce a performance ratio for country comparison by calculating GHG emissions over agricultural production for 2015 and using the global distribution as benchmark. The information from both measurements serves to identify various country and sub regional situations. The findings illustrate that countries with performance ratios in the top 25% and under the best-case elasticity scenario (of strong decoupling) are not necessarily the same as the ones usually identified under factor productivity analyses, suggesting that environment-specific policy incentives and tools play a key role in enhancing sustainable agricultural production. Another major finding is that very few countries in the region (and worldwide) are able to offset agriculture emissions with land use-related carbon sequestration practices. Lastly, the evidence on small Caribbean island-states reporting the worst-case elasticity scenario (of strong negative decoupling) and performance ratios close to the world median, further supports the need for development plans related to climate change mitigation and adaptation in this sub region. [ABSTRACT FROM AUTHOR]

Agriculture represents about 11% of global anthropogenic greenhouse gas emissions (GHGe). Many climate change mitigation strategies have been evaluated in Mediterranean agroecosystems, including their soil organic carbon sequestration potential. High residue yielding old varieties could constitute a useful alternative, especially for organic farming, which lacks specific genetic material. In this study, old and modern wheat varieties were evaluated under organic (ORG) and conventional (CON) management during a 3-year field experiment under rainfed Mediterranean conditions. Field measurements of biomass components, literature emission factors, and soil organic carbon modeling were combined in an attributional Life Cycle Assessment, in order to estimate GHGe from “cradle to farm gate”. The resulting yield-based carbon footprints of old wheat varieties were significantly lower than those of modern varieties both under CON management, decreasing from 263 to 144 g CO 2 e kg −1 , and under ORG management, decreasing from 29 to −43 g CO 2 e kg −1 . Our results indicate that climate change mitigation strategies in Mediterranean rainfed cereal cropping systems should focus on diminishing GHGe from machinery and fertilizer use, and promoting carbon sequestration. The combination of organic management and old cereal varieties can constitute a promising climate change mitigation strategy in these systems, as low area-scaled GHGe of organic management are combined with enhanced carbon sequestration and a good yield performance of old varieties under these conditions. [ABSTRACT FROM AUTHOR]

Wood and other bio-based building materials are often perceived as a good choice from a climate mitigation perspective. This article compares the life cycle assessment of the same multi-residential building from the perspective of 16 countries participating in the international project Annex 72 of the International Energy Agency to determine the effects of different datasets and methods of accounting for biogenic carbon in wood construction. Three assessment methods are herein considered: two recognized in the standards (the so-called 0/0 method and −1/+1 method) and a variation of the latter (−1/+1* method) used in Australia, Canada, France, and New Zealand. The 0/0 method considers neither fixation in the production stage nor releases of biogenic carbon at the end of a wood product's life. In contrast, the −1/+1 method accounts for the fixation of biogenic carbon in the production stage and its release in the end-of-life stage, irrespective of the disposal scenario (recycling, incineration or landfill). The −1/+1 method assumes that landfills offer only a temporary sequestration of carbon. In the −1/+1* variation, landfills and recycling are considered a partly permanent sequestration of biogenic carbon and thus fewer emissions are accounted for in the end-of-life stage. We examine the variability of the calculated life cycle-based greenhouse gas emissions calculated for a case study building by each participating country, within the same assessment method and across the methods. The results vary substantially. The main reasons for deviations are whether or not landfills and recycling are considered a partly permanent sequestration of biogenic carbon and a mismatch in the biogenic carbon balance. Our findings support the need for further research and to develop practical guidelines to harmonize life cycle assessment methods of buildings with bio-based materials. [Display omitted] • Life cycle assessments of the same multi-residential building were carried out by experts from 16 countries. • Effects of methods and datasets of biogenic carbon accounting in wood construction were identified. • Different end-of-life scenarios (incineration, landfill, recycling) cause variations in the results. • Different interpretations of the permanence of storing biogenic carbon in landfills also cause variations in the results. • The input and output flows of biogenic carbon must be balanced to correctly assess its climate change impacts. [ABSTRACT FROM AUTHOR]

Carbon capture (CC), along with the efforts to reduce carbon emissions at the source, is a major action toward the mitigation of climate change and global warming due to emissions of greenhouse gases (GHGs). Carbon emissions amount to 36.3 Gt-CO 2 in 2021 from 31.5 Gt-CO 2 in 2022, with a drop of about 1.5 Gt-CO 2 in 2020 relative to 2019 due to the COVID-19 pandemic. The carbon emissions originate from heat and power, transportation, process industries, and residential activities constitute 47.7, 24.9, 18.9, and 8.5% of the total emissions, respectively. The process industries represent the second large-scale point-source of carbon emissions next to heat and power. Additionally, the process industries have high-intensity carbon emissions up to 0.6–0.8 t-CO 2 /t-cement, 1.4–2 t-CO 2 /t-steel, and 2.7–99.2 kg CO 2 /bbl, with flue gas streams having high CO 2 concentration up to 30%. In comparison to 0.4 t-CO 2 /MWh and 3–16% CO 2 in the flue gas from heat and power facilities, these process industries present a highly effective target for CC application. This work reviews and critically discusses the large-scale application of CC to different process industries, namely, cement, iron and steel, oil refinery, and chemicals. CC can be achieved by three main approaches, i.e., post-combustion, pre-combustion, and oxyfuel combustion. Post-combustion and chemical-looping are the common CC approaches utilized in process industries, with the first being widely applied due to its ease of incorporation, and the latter is commonly used in the cement industry. CC with the capacity in the range of 0.4–2 Mt-CO 2 /yr is planned for cement plants relative to current capacities of 75 kt-CO 2 /yr. Similarly, CC capacity up to 0.8 Mt-CO 2 /yr has been integrated into iron and steel plants, in which captured CO 2 is utilized for enhanced oil recovery (EOR) applications. In the oil and gas industry, CC has been widely utilized, in the context of gas purification, being an essential gas processing unit, with CC capacities up to 1.4 Mt-CO 2 /yr, and plans to reach 4 Mt-CO 2 /yr. CC cost is the main challenge for the widespread implementation of CC in process industries with a wide range of reported costs of USD9.8-250/t-CO 2 depending on the process industry and the CC technology used. [Display omitted] • Process industries emit about 18.5% of the global carbon emissions. • Cement, iron & steel, and oil refining are the major CO 2 emitting processes. • Carbon capture (CC) is a major mitigation action of climate change. • The current process industry's CC capacity of 7 Mt-CO 2 /y has to increase to the Gt-CO 2 /y scale. • CC cost and integrability to existence processes present the main challenges. [ABSTRACT FROM AUTHOR]

Abstract: Climate change mitigation is a dynamic area that, as it is addressed, brings new challenges to other environmental aspects. Carbon capture and storage (CCS) plants are the latest development in a series of environmental controls and have some distinctive features that could potentially lead to other wider environmental problems. Whilst CCS represents a significant step towards cutting greenhouse gas emissions, consideration needs to be given to the potential wider environmental consequences especially in terms of pollutant emissions and local air quality impacts. Challenges remain for existing plants which will need to consider the most cost-effective strategies for installation of CCS plant balanced against managing air quality impacts as dispersion characteristics change. In the case of post-combustion carbon dioxide (CO2) capture technology, which is the focus of this paper, removal of CO2 from the main flue gas stream requires diversion of the flue gas through the CCS process, before it arrives at the exhaust stack. This flue gas stream may be all or part of the total plant flow or for multi-unit plants may be diverted from specific power generation units into the CCS plant before exhausting to atmosphere, either through returning back to the existing stack or through a new dedicated stack. This diversion and subsequent emission in itself poses an engineering challenge. In particular, the integration of the CCS process with the existing plant must also ensure that the diverted flue gas still achieves adequate dispersion as it contains residual levels of pollutants such as nitrogen oxides (NOx) and sulphur dioxide (SO2), despite the fact that the CCS process itself may reduce some of these pollutant levels further as a process by-product. Power plants which incorporate CCS will still be required to adhere to the appropriate pollutant emission limits and ensure effective dispersion to minimise the risk of breaching local air quality standards. This paper draws on experience gained through post-combustion CCS projects and addresses the potential effects of CCS on air quality, in the case of carbon capture retrofits. The findings of this paper are relevant to project developers, power generators and policymakers globally who have an interest in the potential for CCS to provide an emissions abatement option for existing thermal assets in the short and long term. [Copyright &y& Elsevier]

Abstract: The deployment of large scale CO2 Capture and Storage (CCS) may depend largely on the emissions price resulting from a greenhouse gas emission trading system. However, it is unknown whether such a trading system leads to a sufficient high CO2 price and stable investment environment for CCS deployment. To gain more knowledge, we soft-linked WorldScan, an applied general equilibrium model for global policy analysis, with MARKAL-NL-UU, a techno-economic energy bottom-up model of the Dutch power generation sector and CO2 intensive industry. Results from WorldScan show that CO2 prices in 2020 could vary between 20 € /t CO2 in a Grand Coalition scenario, in which all countries accept greenhouse gas targets from 2020, to 47 € /t CO2 in an Impasse scenario, in which EU-27 continues its one-sided emission trading system without the possibility to use the Clean Development Mechanism. Results from MARKAL-NL-UU show that an emission trading system in combination with uncertainty does not advance the application of CCS in an early stage, the rates at which different CO2 abatement technologies (including CCS) develop are less crucial for introduction of CCS than the CO2 price development, and the combination of biomass (co-)firing and CCS seems an important option to realise deep CO2 emission reductions. [Copyright &y& Elsevier]

Abstract: It is regularly argued that CCS deployment is more likely to occur in developed countries associated with high fossil fuels dependence levels, Greenhouse Gases (GHG) emissions sources and to the implementation of specific taxes to GHG. Somewhat counter-intuitively, though, two of the most progressive countries with respect to CCS deployment, Norway and Brazil, only partially fulfill these criteria. Our preliminary analysis suggests that CCS in both cases has been applied as a strategic tool for economic competitiveness, rather than a climate change mitigation option, with public and/or private regulatory arrangements providing initial incentives to take the technology off the ground. This has important implications for policy making since it, by alter our notion of the drivers for action, may call for alternative configurations of incentive structures and policy instruments. [Copyright &y& Elsevier]

Assessing the contribution of terrestrial carbon sequestration to climate change mitigation requires integration across scientific and disciplinary boundaries. A comprehensive analysis incorporating ecologic, geographic and economic data was used to develop terrestrial carbon sequestration estimates for agricultural soil carbon, reforestation and pasture management. These estimates were applied in the MiniCAM integrated assessment model to evaluate mitigation strategies within policy and technology scenarios aimed at achieving atmospheric greenhouse gas stabilization by 2100. Terrestrial sequestration reaches a peak rate of 0.5–0.7GtCyr−1 in mid-century with contributions from agricultural soils (0.21GtCyr−1), reforestation (0.31GtCyr−1) and pasture (0.15GtCyr−1). Sequestration rates vary over time and with different technology and policy scenarios. The combined contribution of terrestrial sequestration over the next century ranges from 23 to 41GtC. [Copyright &y& Elsevier]