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The elevated level of carbon dioxide in the atmosphere has become a pressing concern for environmental health due to its contribution to climate change and global warming. Simultaneously, the energy crisis is a significant issue for both developed and developing nations. In response to these challenges, carbon capture, sequestration, and utilization (CCSU) have emerged as promising solutions within the carbon-neutral bioenergy sector. Numerous technologies are available for CCSU including physical, chemical, and biological routes. The aim of this study is to explore the potential of CCSU technologies, specifically focusing on the use of microorganisms based on their well-established metabolic part. By investigating these biological pathways, we aim to develop sustainable strategies for climate management and biofuel production. One of the key novelties of this study lies in the utilization of microorganisms for CO 2 fixation and conversion, offering a renewable and efficient method for addressing carbon emissions. Algae, with its high growth rate and lipid contents, exhibits CO 2 fixation capabilities during photosynthesis. Similarly, methanogens have shown efficiency in converting CO 2 to methane by methanogenesis, offering a viable pathway for carbon sequestration and energy production. In conclusion, our study highlights the importance of exploring biological pathways, which significantly reduce carbon emissions and move towards a more environmentally friendly future. The output of this review highlights the significant potential of CCSU models for future sustainability. Furthermore, this review has been intensified in the current agenda for reduction of CO 2 at considerable extends with biofuel upgrading by the microbial-shift reaction., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Greenhouse gas (GHG) emissions, particularly anthropogenic emissions, are the primary drivers of climate change. The cultivation of microalgae represents a highly promising strategy for mitigating atmospheric GHG levels. The growth characteristics and GHG mitigation capabilities of Tetradesmus obliquus PF3 were investigated in domestic wastewater at a thermal power plant. The maximum cell density and productivity were 1.52 ± 0.01 g L -1 and 0.33 ± 0.01 g L -1 day -1 , respectively. Utilizing a serial configuration of two reactors, the elimination efficiency of NO and CO 2 attained values of 78 ± 4% and 14 ± 4%, respectively. NO concentration at the outlet was less than 24.6 ± 2.9 mg m -3 , meeting the latest Chinese discharge limits. Besides, the recovery efficiency of NO and CO 2 increased to 77 ± 8% and 2.24 ± 0.04%, respectively, compared to that of the single reactor (40 ± 3%, 0.9 ± 0.0%). A removal efficiency of over 90% was achieved for TN and TP in domestic wastewater. The concentrations of COD (76.5 mg L -1 ), NH 4 + -N (0.9 mg L -1 ), TN(6.31 mg L -1 ), and TP (0.35 mg L -1 ) in effluent were below the thresholds of 100 mg L -1 , 25 mg L -1 , none data, and 3 mg L -1 , respectively, complying with the Chinese Discharge Standard (Class II criteria set forth) for Municipal Wastewater Treatment Plants Pollutants. The harvested biomass exhibited a high content of carbohydrates and proteins, making it a viable feedstock for biofuels and bio-fertilizers. Our results demonstrate that Tetradesmus obliquus PF3-based flue gas treatment technology can simultaneously realize GHG removal, wastewater bio-remediation, and biomass recovery., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

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 CO 2 -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 CO 2 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., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study investigates how carbon dioxide emissions, natural gas, energy consumption, energy investment, coal and crude oil, and per capita exports affected the economic growth of the United States from 1993 to 2023 using the Vector Error Correction (VEC) model. The findings highlight the importance of exports and energy investment in driving both short- and long-term economic growth, while also highlighting interactions between carbon emissions, coal use and crude oil. It was determined that changes in natural gas and exports affected energy investment in the short term, while coal and exports affected natural gas. These results provide valuable information about the dynamics of the American economy and contribute to our understanding of the complex interactions between various factors and their effects on economic growth, offering implications for further research and policy development to promote sustainable economic development., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Globally, the release of greenhouse gases primarily carbon dioxide (CO 2 ) 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 CO 2 concentration has been claimed to lead to significant factors such as global warming potential (GWP) and climate change effects.  An increase in atmospheric CO 2 concentrations is  a  serious threat to the environment. Recent research efforts have focused on mitigating emissions from anthropogenic point sources. Adsorption-based post-combustion CO 2 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, CO 2 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., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The effectiveness of an aquaponic system significantly relies on the habitat provided for both the fish and plants. As an integral component of aquaponics, hydroponic cultivation benefits greatly from the controlled environment of a greenhouse. Within this environment, factors such as temperature, carbon dioxide levels, humidity, and light can be carefully adjusted to maximize plant growth and development. This precise regulation ensures an ideal growing environment, fostering the flourishing of plants and contributing to the overall success of the aquaponic ecosystem. This study presented a control approach for an aquaponic greenhouse system. It aims to keep the greenhouse climate parameters (temperature, CO 2 concentration, and humidity) at their ideal levels. The proposed control strategy is a two-layered mechanism in which the first layer presents an optimization framework using particle swarm optimization (PSO) algorithm to give the setpoints for the controller, and the second layer demonstrates a constrained discrete model predictive control (CDMPC) strategy to maintain the desired trajectories received from the optimization layer. To validate the results obtained using PSO, this study incorporates genetic algorithms (GA) and assesses their performance in comparison. Given similar computational efficiency and low computational time for both algorithms, the optimal values identified by particle swarm optimization (PSO) are adopted as the setpoints. Two performance criteria, relative average deviation (RAD) and mean relative deviation (MRD), are derived to evaluate the tracking performance of the proposed CDMPC controller under external disturbances. A comparison of the proposed CDMPC with the PI controller is also offered. According to the comparison results, our proposed CDMPC performs better than the PI controller with lower RAD values (temperature, 1.1315; CO 2 concentration, 0.9225; humidity, 2.547) and MRD values (temperature, 0.315; CO 2 concentration, 0.25; humidity: 1.013). The controller is validated to be efficient by its strong control performance, highlighted by robustness, efficient setpoint tracking, and adequate disturbance rejection. This novel approach might prove to be a useful technique for developing environmental control strategies that can be used for potentially boosting production rates of aquaponic greenhouse systems, maximizing profitability, and reducing labor needs. By maintaining optimal conditions, it can enhance ecosystem health, improve yields, and streamline operations, paving the way for greater system performance and sustainability., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Four species of shellfish, blue mussel (Mytilus galloprovincialis), Pacific abalone (Haliotis discus hannai), zhikong scallops (Chlamys farreri), and Pacific oyster (Crassostrea gigas), were exposed to decoupled carbonate system variables to investigate the impacts of different seawater carbonate parameters on the CO 2 excretion process of mariculture shellfish. Six experimental groups with two levels of seawater pH (pH 8.1 and pH 7.7) and three levels of total alkalinity (TA = 1000, 2300, and 3600 μmol/kg, respectively) were established, while pH 8.1 and TA = 2300 μmol/kg was taken as control. Results showed that the CO 2 excretion rates of these tested shellfish were significantly affected by the change in carbonate chemistry (P < 0.05). At the same TA level, animals incubated in the acidified group (pH 7.7) had a lower CO 2 excretion rate than those in the control group (pH 8.1). In comparison, at the same pH level, the CO 2 excretion rate increased when seawater TA level was elevated. No significant correlation between the CO 2 excretion rate and seawater pCO 2 levels (P > 0.05) was found; however, a significant correlation (P < 0.05) between CO 2 excretion rate and TA-DIC (the difference between total alkalinity and dissolved inorganic carbon) was observed. Blue mussel has a significantly higher CO 2 excretion rate than the other three species in the CO 2 excretions per unit mass of soft parts, with no significant difference observed among these three species. However, in terms of CO 2 excretion rate per unit mass of gills, abalone has the highest CO 2 excretion rate, while significant differences were found between each species. Our studies indicate that the CO 2 buffering capacity impacts the CO 2 excretion rate of four shellfish species largely independent of pCO 2 . Since CO 2 excretion is related to acid-base balancing, the results imply that the effects of other carbonate parameters, particularly the CO 2 buffering capacity, should be studied to fully understand the mechanism of how acidification affects shellfish. Besides, the species difference in gill to soft parts proportion may contribute to the species difference in responding to ocean acidification., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The urgent need to address global carbon emissions and promote sustainable energy solutions has led to a growing interest in carbon dioxide (CO 2 ) conversion technologies. Among these, the transformation of CO 2 into methanol (MeOH) has gained prominence as an effective mitigation strategy. This review paper provides a comprehensive exploration of recent advances and applications in the direct utilization of CO 2 for the synthesis of MeOH, encompassing various aspects from catalysts to market analysis, environmental impact, and future prospects. We begin by introducing the current state of CO 2 mitigation strategies, highlighting the significance of carbon recycling through MeOH production. The paper delves into the chemistry and technology behind the conversion of CO 2 into MeOH, encompassing key themes such as feedstock selection, material and energy supply, and the various conversion processes, including chemical, electrochemical, photochemical, and photoelectrochemical pathways. An in-depth analysis of heterogeneous and homogeneous catalysts for MeOH synthesis is provided, shedding light on the advantages and drawbacks of each. Furthermore, we explore diverse routes for CO 2 hydrogenation into MeOH, emphasizing the technological advances and production processes associated with this sustainable transformation. As MeOH holds a pivotal role in a wide range of chemical applications and emerges as a promising transportation fuel, the paper explores its various chemical uses, transportation, storage, and distribution, as well as the evolving MeOH market. The environmental and energy implications of CO 2 conversion to MeOH are discussed, including a thermodynamic analysis of the process and cost and energy evaluations for large-scale catalytic hydrogenation., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Sludge produced in sewage treatment plants is an important source of organic matter to be used in anaerobic digestion to produce energy-rich biogas. The biogas produced in anaerobic digesters has a critical impact on achieving carbon neutrality and improving energy self-sufficiency. After effective upgrading, biogas can be converted into biomethane with an increased CH 4 content, resulting in a higher volumetric energy value. Upgrading biogas to biomethane thus not only improves its energy content but also broadens its potential uses. In this study, it was aimed at enrich CH 4 by removing dissolved CO 2 from the digestate using a vacuum, leveraging the solubility differences of gases in liquid. In this context, two digesters (R-T and R-C) were operated for 194 days, and the effect of vacuum on in-situ methane enrichment was investigated. The vacuum was only applied to the test reactor (R-T), and the CH 4 percentage was increased from 63 to 87, 80, and 75% in the vacuum exposure time intervals of 30, 10, and 5 min, respectively. Extended durations were not tested, as the rate of enrichment decreased sharply after 30 min. The maximum energy requirement of a vacuum application was estimated at 0.124 kWh/m 3 methane. Conversely, vacuum application did not cause any deterioration in biogas production, and the methane yields were similar in both reactors., (© 2024. The Author(s).)

Meeting the energy and water demands of remote areas has created significant challenges globally. To address this issue, the utilization of hybrid energy-water systems, integrated with renewable energies, has been highlighted as a viable solution. This work has been focused on the multi-objective optimization of a hybrid energy system, encompassing photovoltaic panels, batteries, diesel generators, and desalination units. The design goals to achieve the optimal configuration include minimizing system costs, reducing carbon dioxide emissions, enhancing the renewable factor, and improving reliability. Also, for the mentioned design goals, the performance of three desalination methods including reverse osmosis (RO), multi-stage flash (MSF), and multiple-effect distillation (MED) was evaluated by Hybrid Optimization of Multiple Energy Resources (HOMER) software. Our findings reveal that the RO desalination method, when combined with renewable energy, outperforms other methods both economically and environmentally. Notably, the RO method reduces net present cost (NPC) by 6.18% and 8.25% and carbon dioxide emissions by 38% and 46%, respectively, compared to MED and MSF methods. Additionally, sensitivity analysis, considering factors such as interest rate, photovoltaic panel cost, battery cost, and fuel cost, was conducted on NPC. The results showed that with a 2% decrease in the interest rate, the amount of NPC increases by about 2.4% due to the increase in the share of renewable energy. Therefore, reducing the interest rate helps to design a system with less carbon dioxide emissions. This work, by highlighting the economic and environmental implications of different desalination methods, as well as key cost factors, contributes to the optimal design of combined energy-water schemes for remote areas., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Homoacetogenesis is an important pathway for bio-utilization of CO 2 ; however, oxygen is a key environmental influencing factor. This study explored the impact of different initial oxygen partial pressures (OPPs) on homoacetogenesis, while implementing low pH regulation enhanced acetic acid (HAc) accumulation under microaerobic conditions. Results indicated that cumulative HAc production increased by 18.2% in 5% OPP group, whereas decreases of 31.3% and 56.0% were observed in 10% and 20% OPP groups, respectively, compared to the control group. However, hydrogenotrophic methanogens adapted to microaerobic environment and competed with homoacetogens for CO 2 , thus limiting homoacetogenesis. Controlling influent pH 5.0 per cycle increased cumulative HAc production by 18.3% and 18.2% in 5% and 10% OPP groups, respectively, compared with the control group. Consequently, regulating low pH effectively inhibited methanogenic activity under microaerobic conditions, thus increasing HAc production. This study was expected to expand the practical application of homoacetogenesis in bio-utilization of CO 2 ., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The current work investigated emerging fields for generating and consuming hydrogen and synthetic Fischer-Tropsch (FT) fuels, especially from detrimental greenhouse gases, CO 2 and CH 4 . Technologies for syngas generation ranging from partial oxidation, auto-thermal, dry, photothermal and wet or steam reforming of methane were adequately reviewed alongside biomass valorisation for hydrogen generation, water electrolysis and climate challenges due to methane flaring, production, storage, transportation, challenges and opportunities in CO 2 and CH 4 utilisation. Under the same conditions, dry reforming produces more coke than steam reforming. However, combining the two techniques produces syngas with a high H 2 /CO ratio, which is suitable for producing long-chain hydrocarbons. Although the steam methane reforming (SMR) process has been industrialised, it is well known to consume significant energy. However, coke production via catalytic methane decomposition, the prime hindrance to large-scale implementation of these techniques for hydrogen production, could be addressed by coupling CO with CO 2 conversion to alter the H 2 /CO ratio of syngas, increasing the reaction temperatures in dry reforming, or increasing the steam content fed in steam reforming. Optimised hydrogen production and generation of green fuels from CO 2 and CH 4 can be achieved by implementing these strategies., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Solvent-based CO 2 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 CO 2 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 CO 2 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 CO 2 capture performance of the system. The results were analyzed on the basis of captured CO 2 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 CO 2 composition. The amine-based CO 2 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., (© 2024. The Author(s).)

Countries around the world have set aggressive carbon emission reduction targets using various carbon reduction technologies to overcome the worsening global climate crisis. However, amid concerns among experts that such aggressive targets are difficult to achieve with existing carbon reduction technology, CCUS technology has gained recognition as an innovative technology, showing great promise in directly removing carbon dioxide and achieving carbon neutrality. This study employed a two-stage network DEA to analyze efficiency at knowledge diffusion and application stages of CCUS technology in relation to country-specific R&D environments. Based on the analysis, the following conclusions were derived. First, countries with higher standards of innovation in science and technology were more focused on quantitative R&D outcomes, making them less efficient in the diffusion and application stages. Second, countries with heavier dependence on manufacturing were less efficient in the diffusion of research outcomes due to difficulties in enforcing strong environmental-friendly policies. Lastly, countries with heavier dependence on fossil fuels were actively promoting CCUS development as a solution to carbon dioxide emissions, and such efforts were a driving factor in the diffusion and application of R&D outcomes. The significance of this study lies in analyzing the efficiency of CCUS technology in terms of knowledge diffusion and application, which are clearly distinct from a quantitative R&D efficiency analysis, thereby serving as a valuable reference in the establishment of country-specific R&D strategies for greenhouse gas reduction., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The development of technologies to capture greenhouse gases (GHGs) like carbon dioxide (CO 2 ) and nitrous oxide (N 2 O) is vital for climate change mitigation. Ionic liquids (ILs), deep eutectic solvents (DES), and natural deep eutectic solvents (NADES) are promising absorbents to abate GHGs emissions. However, their high viscosity limits the gas-liquid contact, as consequence of the mass transfer. To overcome this, their impregnation onto porous silica gel has been carried out, increasing the gas-liquid contact area. The present study analyzes the effect of size particle of silica gel impregnated with ILs, DES, and NADES over the CO 2 and N 2 O capture at atmospheric conditions. The degree of impregnation of silica particles was determined by thermogravimetric analysis (TGA). The identification of functional groups present on the surface of silica, ILs, DES, and NADES was performed using Fourier-transform infrared spectroscopy (FTIR), and their crystalline structure was determined by X-ray diffraction (XRD). The partition coefficient of CO 2 and N 2 O between gas and ILs, DES, and NADES was determined by a static headspace method. Results show that the degree of solvent impregnation on silica gel ranged from 36.8 to 43.0% w/w, the partition coefficient of CO 2 in the impregnated silica varied from 0.005 to 0.067, and for N 2 O, from 0.005 to 0.032. This suggests that impregnated particles have a greater affinity for N 2 O compared to CO 2 . Using impregnated particles requires only 40% of the bulk solvent to achieve a similar GHG capture capacity compared to using bulk solvents., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Alkali sludge (AS) is waste abundantly generated from solar photovoltaic (PV) solar cell industries. Since this potential basic material is still underutilized, a combination with NiO catalyst might greatly influence coke resentence, especially in high-temperature thermochemical reactions (Arora and Prasad, RSC Adv. 6:108,668-108688, 2016). This paper investigated alkaline sludge containing 3CaO-2SiO 2 doped with well-known NiO to enhance the dry reforming of methane (DRM) reaction. The wet-impregnation method was used to prepare the xNiO/AS (x = 5-15%) catalysts. Subsequently, all catalysts were tested by using X-ray diffraction (XRD), nitrogen adsorption/desorption (BET), temperature-programmed reduction of hydrogen (H 2 -TPR), temperature-programmed desorption of carbon dioxide (TPD-CO 2 ), field emission scanning electron microscopy (FESEM-EDX), and X-ray photoelectron spectroscopy (XPS). The spent catalysts were analyzed by thermogravimetric analysis (TGA/DTG), transmission electron microscopy (TEM), and temperature-programmed oxidation (TPO). The catalytic performance of xNiO/AS catalysts was investigated in a fixed bed reactor connected with gas chromatography thermal conductivity detector (GC-TCD) at a CH 4 :CO 2 flow rate of 30 mL -1 during a 10-h reaction by following (Shamsuddin et al., Int. J. Energy Res. 45:15,463-15,480, 2021d). For optimization parameters, the effects of NiO concentration (5, 10, and 15%), reaction temperature (700, 750, 800, 850, and 900 °C), catalyst loading (0.1, 0.2, 0.3, 0.4, and 0.5 g), and gas hourly space velocity (GHSV) range from 3000, 6000, 9000, 12,000, and 15,000 h -1 were evaluated. The results showed that physical characteristics such as BET surface area and porosity do not significantly impact NiO percentages of dispersion, whereas chemical characteristics like reducibility are crucial for the catalysts' efficient catalytic activity. Due to the active sites on the catalyst surface being more accessible, increased NiO dispersion resulted in higher reactant conversion. The catalytic performance on various parameters that showed 15%NiO/AS exhibited high reactant conversion up to 98% and 40-60% product selectivity in 700 °C, 0.2 g catalyst loading, and 12,000 h -1 GHSV. According to spent catalyst analyses, the catalyst was stable even after the DRM reaction. Meanwhile, increased reducibility resulted in more and better active site formation on the catalyst. Synergetic effect of efficient NiO as active metal and medium basic sites from AS enhanced DRM catalytic activity and stability with low coke formation., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Tourism development is generally agreed upon to be a key tool in promoting economic growth, and green development has emerged as a significant idea and an efficient approach to accomplish this goal in a manner that is environmentally responsible. It is common knowledge that making the switch to renewable sources of energy may act as a catalyst for economic development in both developed and developing nations. Therefore, people all over the globe are beginning to realize the significance of advancing renewable energy's rising importance that suggests that it will be used extensively in the years to come. The purpose of this study is to examine the effect that increasing tourism and adopting renewable energy sources impact on green economic growth development in the region using the AMG test BRICS nations from 2001 to 2022. This research additionally makes use of a rigorous check by means of the CCEMG exam and the DCCEMG test. According to the findings, green economic growth is influenced favorably by the expansion of the tourist industry, renewable energy, and the digital economy, but urbanization and the rise financial industry are detrimental to green economic growth. D-H panel causality test results show that tourism development is causally related to green economic growth, green economic growth to urbanization, and green economic growth to the usage of renewable energy sources. According to these results, the management authorities of BRICS nations should embrace policies of green growth while also controlling environmental pollution in order to achieve sustainable economic development whereas in rural areas. The findings have major policy implications for the nations that make up the BRICS bloc. These implications pertain to the enhancement of tourist development, the digital economy (DIG), and financial institutions, all of which have the potential to improve environmental quality., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The Chengdu-Chongqing twin-city economic circle is a vital growth pole and a new power source for Chinese high-quality development. Studying the spatial-temporal characteristics of carbon emissions and the role of factors affecting them under the transportation perspective is of great significance for this region to realize the carbon peak and carbon neutrality and to formulate carbon emission reduction policies. We use the exploring spatial data analysis (ESDA) and spatial regression model combined with the STIRPAT model, and research finding: (1) The total carbon emissions in the research area gradually increased from 2014 to 2020, but the growth rate showed a significant decline in 2019. (2) There is significant spatial heterogeneity of carbon emissions in the study area; the hotspot areas of total carbon emissions are in Chongqing and Chengdu, forming a high-low aggregation of carbon emissions. Per capita carbon emissions show a high trend in the southwest and a low in the northeast. (3) From the factors of transportation perspective, highway density and private vehicles have a positive impact on carbon emissions, and urban road areas and public transportation have a very significant inhibition of carbon emissions and a spatial spillover effect. (4) Other factors, such as population size, national economic development, urbanization level, and industrial structure, all have a positive effect on carbon emissions, and disposable income has a negative effect on carbon emissions., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The anthropogenic impact of the water and CO 2 exhaled by visitors was studied in the show caves of the Moravian Karst (Czech Republic), especially in the Balcarka and Výpustek Caves. Two alternative models based on (1) the known/presumed composition of the breathed air and physical activity of visitors and (2) the detailed monitoring microclimatic data were proposed. The CO 2 fluxes of 2.4 × 10 -4 and (2.0-3.9) × 10 -4  mol person -1  s -1 and the water vapor fluxes of (3.2-8.9) × 10 -3 and (0.6-1.2) × 10 -2  g person -1  s -1 were found for a slightly increased physical load. The total attendance and cave tour duration were the main driving factors. For the available data on attendance and accessibility periods, the total mass of water vapor exhaled by visitors in all show caves in the Moravian Karst was estimated between 9.6 × 10 6 and 4.3 × 10 8  g with significant seasonality. According to the geochemical model, this mass of water is capable of dissolving 1280 to 59,038 g of calcite, assuming a mean winter and summer CO 2 concentration in the cave air of 1000 and 3000 ppmv. The larger extent of water condensation can lead to the so-called condensation corrosion, whereas the lower extent of condensation probably causes a recrystallization of calcite on the surface of speleothems and rocks., (© 2024. The Author(s).)

The proliferation of carbon dioxide (CO 2 ) emissions has resulted in significant environmental challenges worldwide, particularly within industrialized nations. The present paper tries to investigate the role of food, beverages, and tobacco in mitigating CO 2 emissions in the top industrial countries. Economic growth and renewable and non-renewable energy consumption are integrated as control variable in the empirical model. The study applied the pooled mean group-autoregressive distributed lag (PMG-ARDL) model proposed by (J Appl Econ, 16:289-326, 2001) and Granger causality test for causalities directions. The empirical outcomes suggest the presence of cross-sectional dependence, and variables are integrated of order one and cointegrated. Long-run estimates revealed the presence of inversed U curve proving the validity of the environmental Kuznets curve. Also, the results show that renewable energy (RE) consumption contribute in reducing emissions, while non-renewable energy (NRE) and food, beverages, and tobacco (FBT) led to increase emissions level in the long run. Granger shows bidirectional long-run relationship between CO 2 emissions, non-renewable energy, and economic growth. Moreover, Granger recorded no causality between food, beverages, and tobacco and any other variable. We recommend that firms engaged in the production of food, beverages, and tobacco products are increasingly urged to make investments in clean technologies powered by renewable energy sources for their manufacturing processes. This is considered a necessary step to achieve a significant reduction in CO 2 emissions over an extended period., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The reduction of the carbon emissions of construction industry is urgent. Therefore, it is essential to accurately predict the carbon emissions of the provincial construction industry, which can support differentiation emission reduction policies in China. This paper proposes a carbon emission prediction model that optimizes the backpropagation (BP) neural network by genetic algorithm (GA) to predict carbon emission of construction industry, or "GA-BP". To begin with, the carbon emissions of construction industry in Sichuan Province from 2000 to 2020 are calculated by the emission factor method. Further, the electricity correction factor is introduced to eliminate the regional difference in electricity carbon emission coefficient. Finally, four factors are selected by the grey correlation analysis method to predict the carbon emission of construction industry in Sichuan Province from 2021 to 2025. The results show that the carbon emissions of construction industry in Sichuan Province have been trending up in the past two decades, with an average increase rate of 10.51%. The GA-BP model is a high-precision prediction model to predict carbon emissions of construction industry. The mean absolute percentage error (MAPE) of the model is only 6.303%, and its coefficient of determination is 0.853. Moreover, the carbon emissions of construction industry in Sichuan Province will reach 8891.97 million tons of CO 2 in 2025. The GA-BP model can effectively predict the future carbon emissions of construction industry in Sichuan Province, which provides a new idea for the green and sustainable development of construction industry in Sichuan Province., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The catalytic conversion of carbon dioxide is one of the important ways to achieve the goal of carbon neutralization, which can be further divided into electrocatalysis, thermal catalysis, and photocatalysis. Although photocatalysis and electrocatalysis have the advantages of mild reaction conditions and low energy consumption, the thermal catalytic conversion of CO 2 has larger processing capacity, better reduction effect, and more complete industrial foundation, which is a promising technology in the future. During the development of new technology from laboratory to industrial application, ensuring the safety of production process is essential. In this work, safety optimization design of equipment, safety performance of catalysts, accident types, and their countermeasures in the industrial applications of CO 2 to methanol are reviewed and discussed in depth. Based on that, future research demands for industrial process safety of CO 2 to methanol were proposed, which provide guidance for the large-scale application of CO 2 thermal catalytic conversion technology., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

As the demand for automotive materials grows more stringent in environmental considerations, it becomes imperative to conduct thorough environmental impact assessments of dual-phase automotive strip steel (DP steel). However, the absence of detailed and comparable studies has left the carbon footprint of DP steel and its sources largely unknown. This study addresses this gap by establishing a cradle-to-gate life cycle model for DP steel, encompassing on-site production, energy systems, and upstream processes. The analysis identifies and scrutinizes key factors influencing the carbon footprint, with a focus on upstream mining, transportation, and on-site production processes. The results indicate that the carbon footprint of DP steel is 2.721 kgCO 2 -eq/kgDP, with on-site processes contributing significantly at 88.1%. Sensitivity analysis is employed to assess the impact of changes in resource structure, on-site energy, CO 2 emission factors, and byproduct recovery on the carbon footprint. Proposals for mitigating carbon emissions in DP steel production include enhancing process gas recovery, transitioning to cleaner energy sources, and reducing the hot metal-to-steel ratio. These findings offer valuable insights for steering steel production towards environmentally sustainable practices., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A circular economy is a regenerative approach that emphasizes resource efficiency, waste reduction, and the reuse of materials for a sustainable world. By adopting circular practices, we can reduce the negative impact of traditional linear economic models on the environment. According to the International Renewable Energy Agency (IRENA), the world is generating only 26% of total energy production from circular practices, which positively impacts environmental health. Therefore, this study aims to evaluate the empirical estimation of circular practices regarding energy on the environment. The current study focuses on the association between the circular economic index, economic growth, trade, digitization, energy use, and the financial development index on the environment in 29 high-income countries from 1990 to 2019. The study employs the second-generation econometric technique Driscoll-Kraay to empirically estimate the association among the variables of interest after confirming cross-sectional dependency within the data set. The study findings reveal that circular practices improve high-income countries' environmental conditions. Furthermore, the study confirms the association between economic growth, financial development index, energy use, trade, and digitization on the environment, and it leads to a more sustainable situation. Policies are drawn based on findings for policymakers toward a sustainable world., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In the complex international society, the economic development and defense construction of BRICS countries have attracted increasing attention. This article incorporates technological innovation, militarization, and environmental change into a unified analytical framework to assess the potential impact of technological progress and defense military expenditure on the environment in BRICS countries. Based on CSD tests, unit root tests, and cointegration tests, this study constructs a CS-ARDL model to examine the long-term and short-term relationships among various variables from 1990 to 2021. The results show that technological innovation, military expenditure, and economic growth can significantly increase ecological footprint in the long run, while in the short term, technological innovation and economic growth significantly increase ecological footprint, and the impact of military expenditure is not significant. It is suggested that BRICS countries should focus on supporting low-carbon technology policies and research and development investment, while also considering the use of cutting-edge technology to improve military intelligence capabilities in order to reduce the negative impact of technological innovation and military activities on the environment., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The balance between human growth, economic prosperity, and the consumption of hydrocarbon energy factors has become a prerequisite for environmental sustainability. However, the complexities of these factors force researchers to work for more viable combinations of such a balance. Therefore, this study attempted to determine the factors driving environmental sustainability in leading populated economies. For this purpose, the Logarithmic Mean Division Index (LMDI) utilized to decompose critical factors such as activity, economy, real density, energy intensity, and suburban effects for the period 1999-2022. Both population and its consequences (economic activity) have been found to be the leading factors behind environmental fluctuations, and energy has a negative impact on hydrocarbon forms, while contributing positively to environmental sustainability with high efficiency and low intensity. Therefore, sustainable demographic and energy transitions can be leading pathways for environmental sustainability in developing economies., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study contributes significantly to the field by utilising the World Economic Policy Uncertainty (WEPU) Index, as devised by (Ahir in Nat Bureau Econ Res 2022), to scrutinise its impact on carbon dioxide emission reporting and performance. Employing the generalised method of moments (GMM) on a substantial dataset of 604 Fortune Global 500 firms spanning from 2005 to 2020, our analysis reveals crucial insights. The research elucidates the dual influence of WEPU Index: a positive correlation with carbon dioxide emission reporting and a negative correlation aimed at mitigating adverse effects and promoting sustainable practices, thereby enhancing firm trust. Moreover, the findings shed light on how companies in emission-intensive industries tend to ramp up carbon dioxide emission reporting, potentially to bolster investor confidence, particularly during high WEPU Index periods. Furthermore, this study uncovers a compelling association between high emitters and lowered carbon dioxide emission performance, stemming from political and social pressures to integrate environmental considerations. Notably, this pressure intensifies during periods of increased WEPU Index. The empirical results presented in this study carry immediate practical implications. Specifically, they offer valuable insights for regulatory bodies and industry associations, guiding the development of enhanced environmental and social reporting regulations and guidelines, particularly concerning carbon emission reporting and performance., (© 2024. The Author(s).)

Financial deepening is important in resource allocation for more productive enterprises, leading to sustainable green growth. Moreover, rapid development in the digital economy and export diversification significantly affect green growth. From this perspective, our study explores the impact of financial deepening, ICT development, and export diversification on green growth in China's economies from 1996 to 2021. The study explores the linkage between financial deepening, ICT development, export diversification, and green growth by employing the nonlinear autoregressive distributed lag (NARDL) approach. The results obtained in the long run are as follows: positive shock in financial deepening brings positive change in green growth, whereas negative shock in financial deepening reduces green growth. In the long run, positive shock in ICT enhances green growth, but negative shock in ICT does not impact green growth. Moreover, positive shock in export diversification brings positive change in green growth, whereas negative shock in export diversification reports an insignificant impact on green growth. Based on findings, it is suggested that financial deepening, ICT development, and export diversification are conducive to sustainable green growth., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To find a way to realize sustainable development, this paper applied a cross-sectional ARDL (CS-ARDL) method to explore the interaction between carbon emissions, economic development, and health care expenditure for OECD countries. Firstly, we conduct a cross-sectional test to check whether the data is confronted with this issue. Secondly, we conduct a panel unit root test and cointegration test to confirm whether the ARDL-based method is suitable for our data. Thirdly, we analyze the results and provide possible explanations. Lastly, we conduct a short-term causality test to detect the connection between different variables. The main conclusion of our study includes: 1) Health care is a necessity in OECD countries. 2) Environmental deterioration places a heavy burden on health care expenditure in OECD countries. 3) Health care expenditure of last year negatively affects health care expenditure. 4) There is a short-run causality relationship from CO 2 , economic development, and dependency rate of youth to health care expenditure in OECD countries. Related policy proposals are provided according to our analysis of the results., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

As the global greenhouse effect intensifies, carbon emissions are gradually becoming a hot topic of discussion. Accurate carbon emissions prediction is an important foundation to realize carbon neutrality and peak carbon dioxide emissions. To accurately predict carbon emissions, a multi-factor combination prediction model based on improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN), bidirectional long short-term memory optimized by lemurs optimizer (LOBiLSTM) and least squares support vector machine optimized by lemurs optimizer (LOLSSVM), named ICEEMDAN-LOBiLSTM-LOLSSVM, is proposed. Firstly, the influencing factors of carbon emissions are selected by Spearman correlation coefficient, and carbon emissions are decomposed into intrinsic mode functions (IMFs) by ICEEMDAN. Secondly, the influencing factors and IMFs are input into LOBiLSTM and LOLSSVM respectively for prediction. Then, the point prediction results are obtained by weighting the prediction results of LOBiLSTM and LOLSSVM. Finally, probability density function of point prediction error is calculated by kernel density estimation, and the interval prediction results are calculated according to different confidence intervals. Carbon emissions of China and Germany are selected to verify the superiority of ICEEMDAN-LOBiLSTM-LOLSSVM. The experiment shows that RMSE, MAE, MAPE, and R 2 of the proposed model are 0.4468, 0.3612, 0.0120, and 0.9839 respectively for China, which is the best among the nine models, as well as for Germany., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Sintering and elutriation are two main problems of the calcium looping process for high-temperature CO 2 capture. In the process of CO 2 capture, the operation temperature is generally higher than the Taman temperature, resulting in the agglomeration and sintering of the sorbents. The traditional sorbent powers need to be granulated for practical application in a circulating fluidized bed to avoid elutriation. By using a new agar-assisted technology to granulate CaO powder incorporated with Mg, Y, and Ce inert supports, the problems of sintering and elutriation can be mitigated within one step. The incorporated inert supports are uniformly dispersed in the CaO/CaCO 3 particles as an inert scaffold, and the inert scaffold is used as a skeleton to resist sintering, alleviate its agglomeration phenomenon, and keep the specific surface area to a certain extent. The Ce-incorporated CaO pellets have been proven to exhibit the best carbonation conversion and sorption capacity. The sorption capacity of 10% CeO 2 -incorporated CaO pellets reached 0.574 g CO 2 /g sorbent, more than 43% higher than that of the pure CaO pellets. In addition, the effects of the solid-liquid ratio during the preparation stage on CO 2 performance were also investigated, demonstrating that a solid-liquid ratio of 1:5 was the optimal ratio to produce satisfying sorbents. The mitigated sintering and achieved spherical CaO pellets greatly promote the practical application of the calcium looping process for CO 2 capture., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Gearing up for green technology innovation (GTI) and natural resources has become even more important in the transition to a zero-emission life, a green economy, and sustainable development goals. This attempt has become a situation that needs to be overpowered much sooner by the European countries, which have encountered challenges in many ways, especially regarding natural resources, energy supply, and the climate crisis. In this vein, the current study follows the novel, robust Method of Moment Quantile-Regression (MM-QR), which successfully yields heterogeneous information structure across quantiles, to examine the determinants of GTI for 15 EU countries over the period of 2003-2018. MM-QR estimation results indicate that the determinants of green technology innovation are heterogeneous across the EU countries. While green growth (GG) has an adverse impact on GTI in middle- and high-GTI countries, the effect of ecological footprint on GTI is positive for countries in the highest-GTI countries. The positive effects of financial development (FD) on GTI are revealed for all countries. Remarkably, environmental taxes have an adverse and positive influence on GTI in the lowest and highest quantile countries, respectively. Finally, renewable energy and greenfield FDI have no effect on GTI. Governments can promote GTI by providing financial resources, in the most immaculate way, to firms that engage in green technology projects, as well as by encouraging these through environmental taxes., (© 2024. The Author(s).)

Urban areas serve as a vital contribution to the global structural change towards renewable and sustainable energy technologies which also influence climate change. The aim of this paper is to identify the adoption roadblocks to renewable and sustainable urban energy technologies. This research has three parts: a mini-systematic literature study was conducted to identify the most prevalent roadblocks. Using total interpretive structural modeling (ISM), the relationships between the roadblocks and the source of causation were then examined. The roadblocks are classified based on their dependence and driving powers using MICMAC analysis in the third part of this research. The principal results and major conclusions demonstrate that all roadblocks are necessary for renewable and sustainable urban energy technologies. The roadblocks at level I are insufficient infrastructure, lack of coordination among authorities, lack of quality and reliable data and information, and competition with non-renewable technologies; roadblocks in level II are lack of skilled and trained personnel, limited public participation, awareness, and consumer interest, and lack of standardized technology; roadblock in level III is high initial investment cost; and lastly, roadblocks in level IV are lack of subsidies and financial support programs and absence of coherent related policies. Furthermore, as a result of the MICMAC analysis, none of the aforementioned roadblocks are classified as autonomous variables, implying that they are all required. The dependent roadblocks to renewable and sustainable energy technologies are defined as lack of coordination among authorities, lack of information, and competition with non-renewable technologies. Moreover, linkage roadblocks have high dependence and driving powers which are insufficient infrastructure, limited awareness and consumer interest, and lack of standardized technology. Lastly, high initial investment costs, lack of subsidies and financial support programs, absence of coherent related policies, and lack of skilled and trained personnel are the driving roadblocks with high driving power however not dependent., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Climate change effect mitigation is a critical priority for top leaders and communities around the globe. Human-induced environmental issues are affecting humankind's standard of living and development potential and the planetary boundaries. Sustainability objectives aim to enhance environmental quality and ensure sustainable development for all by eliminating social inequalities. This study examines the complex relationships between demographic features, foreign direct investment, technological innovation, and ecological footprint, emphasizing the relevance of population aging, population density, and urbanization in this context. The research uses a selection of emerging European economies during 1995-2018. The reasons for countries' selection are related to the increasing rate of population aging in European countries, the attractiveness for foreign direct investment, the economic growth, and the technological advancement potential these emerging countries possess. In order to investigate the long-run relationship between the selected variables, the study tests the cross-section dependence, homogeneity, and cointegration and uses Konya tests to determine panel causality. Based on Konya methodology, differences between countries in the panel are evidenced and discussed accordingly. Our findings confirm the long-run relationship between environment, technological innovation, population aging, and FDI. The results of this research are highly relevant for policymakers in selected countries for identifying the set of correlations and the relevance of various variables in such national economies. Demographic features such as population aging and population density are critical for Europe, and the results show the impact on the ecological footprint., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The effort towards a greener future will entail a shift to more environmentally friendly alternatives of many human activities. Within this context, the path towards a decarbonized society in general, and industrial decarbonization in particular, will require using low carbon solutions and/or capturing carbon emissions at the source. This flux of captured carbon will then require management and one option is to store it in concrete. The incorporation of the captured CO2 can be done during the mixing and/or curing. While the latter is more efficient and effective in terms of the amount of CO2 incorporated, it is limited to concrete in elements that are compatible with chamber curing. In practice, this would be restricted to the concrete pre-fabrication industry and, most probably, only to small size elements. Despite the lower performance, incorporation of CO2 into concrete during the mixing stage is a relatively universal alternative. The present research effort reveals that the latter solution is beneficial from an environmental point of view, with an estimated yearly carbon storage of 23 million tonnes worldwide against emissions of 2.5 million tonnes to do it., (© 2024. The Author(s).)

Green innovations are the most critical factor in promoting environmental sustainability worldwide. Trade can speed up the adoption of green innovations by facilitating the transfer of information, skills, and technology. However, trade policy uncertainty can create significant challenges for businesses investing in eco-innovations, leading to increased risk, reduced investment, and slower progress toward sustainable technologies. Recently, a growing number of researchers have shown their interest in finding the factors that can impact green innovations, but none have investigated the influence of trade policy uncertainty on green innovations in the USA and China. In addition, none of the past studies has relied on the nonlinear assumption. This analysis fills these gaps by examining the nonlinear impacts of trade policy uncertainty on eco-innovations in China and the USA over 2000Q1-2021Q4 by employing a nonlinear ARDL model. The finding reveals that a positive shock in trade policy uncertainty results in a decrease in green innovation in the USA and China, while a negative shock in trade policy uncertainty leads to an increase in green innovation in the USA over the long run. The nonlinear models also indicate that a positive shock in trade policy uncertainty harms green innovation in both the USA and China in the short run. The robustness of these results is confirmed by the NQARDL model, which confirms that an upsurge in trade policy uncertainty lowers green innovation in most quantiles in the USA and China in the short and long run. Conversely, negative shocks in trade policy uncertainty stimulate green innovation at most quantiles in both China and the USA, in the short and long run. Thus, policymakers need to consider the potential impact of trade policies on eco-innovations and work to create stable and predictable trade environments that support the growth of renewable technologies and other sustainable solutions., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

High-temperature solid adsorbent Li 4 SiO 4 has received broad attention due to its high theoretical adsorption capacity, high regeneration capacity, and wide range of raw materials for preparation. In this paper, a Li 4 SiO 4 adsorbent was prepared by MCM-48 as the silica precursor and modified by doping with metal ions (Ca 2+ and Na + ) for high-temperature capture of low-concentration CO 2 . The results showed that the surface of the Ca-doped (or Na-doped) Li 4 SiO 4 adsorbent developed some particles that are primarily composed by Li 2 CaSiO 4 (or Li 3 NaSiO 4 ). Furthermore, the grains of the adsorbents became finer, effectively increasing the specific surface area and enhancing adsorption performance. Under 15 vol% CO 2 , the maximum CO 2 adsorption was 25.63 wt% and 32.86 wt% when the Ca 2+ doping amount was 0.06 and the Na + doping amount was 0.12, respectively. These values were both higher than the adsorption capacity before the metal ion doping. After 10 adsorption/desorption cycles, the adsorption capacity of Na-doped Li 4 SiO 4 increased by 9.68 wt%, while that of Ca-doped Li 4 SiO 4 decreased by 7.98 wt%. This difference could be attributed to the easy sintering of the Ca-containing adsorbent. Furthermore, a biexponential model was used to fit the CO 2 adsorption curve of the adsorbent in order to study the adsorption kinetics. Compared to the conventional Li 4 SiO 4 , the Ca/Na-doped adsorbent offers several advantages, such as a high CO 2 adsorption capacity and stable cycling ability., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Solid waste management is a critical issue worldwide. Effectively utilizing these solid waste resources presents a viable solution. This study focuses on Iron ore tailings (IOTs), a solid waste generated during iron ore processing, which can be used as supplementary cementitious materials (SCMs) but have low reactivity, hindering their large-scale application in concrete production. To address this, ternary SCMs were prepared using ceramic powder (CP) and steel slag (SS) to enhance the performance of concrete incorporating IOTs. The study found that the synergistic effect of CP and SS significantly improved the compressive strength of concrete, with a notable increase of up to 21% compared to concrete with IOTs alone. Mercury intrusion porosimetry (MIP) and backscattering electron (BSE) analyses revealed that the ternary SCMs significantly optimized the characteristics of the interfacial transition zone (ITZ), which in turn enhanced the compressive properties of the concrete. This contributed to maintaining the structural integrity of the concrete, even amidst variations in the pore structure. Importantly, the incorporation of ternary SCMs led to a 23% reduction in carbon emissions, from 400.01 kg CO 2 /m 3 to 307.48 kg CO 2 /m 3 , and elevated eco-strength efficiency from 0.1 to 0.14. The study highlights the role of multi-material synergy in developing composite SCMs systems, fostering the sustainable advancement of green building materials., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The rapid rise in climate and ecological challenges have allowed policymakers to introduce stringent environmental policies. In addition, financial limitations may pose challenges for countries looking to green energy investments as energy transition is associated with geopolitical risks that could create uncertainty and dissuade green energy investments. The current study uses PTR and PSTR as econometric strategy to investigate how geopolitical risks and financial development indicators influence energy transition in selected industrial economies. Our findings indicate a non-linear DCPB-RE relationship with a threshold equal to 39.361 in PTR model and 35.605 and 122.35 in PSTR model. Additionally, when the threshold was estimated above, financial development indicators and geopolitical risk positively impacts renewable energy. This confirms that these economies operate within a geopolitical context, with the objective of investing more in clean energy. We report novel policy suggestion to encourage policymakers promoting energy transition and advance the sustainable financing development and ecological sustainability., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Electric arc furnace dust (EAFD) is a hazardous by-product of steel production. As global steel output increases, substantial amounts of EAFD are produced, which causes significant environmental issues. EAFD contains quantities of Fe and Zn, which could be reused as raw materials in the steelmaking process. However, zinc oxides can be reduced and vaporized during this process, forming zinc vapor that contaminates equipment surfaces and causes damage. Consequently, various pyrometallurgical methods have been proposed for zinc removal from EAFD. Due to the extensive usage of carbonaceous materials, these methods contribute to significant CO 2 , raising concerns about greenhouse gas emissions. Microwave heating offers an efficient, energy-saving, and environmentally friendly alternative to pyrometallurgical approaches. EAFD can generate heat under microwave irradiation without carbon addition, which means the CO 2 emissions can be reduced by replacing the reductant in the microwave heating process. Furthermore, microwaves enhance zinc removal reactions to a certain extent, resulting in higher efficiency. Thus, employing microwave heating for EAFD processing has significant potential for future development. This paper reviews recent research on using microwave heating for zinc removal from EAFD, focusing on the heating behavior of EAFD in microwaves and the mechanisms of zinc removal. This review will be crucial for researchers working on processing EAFD using microwave heating and could help guide the development of more sustainable and efficient methods., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Monochlorodifluoromethane (HCFC-22) has been identified as a significant contributor to the depletion of the Earth's ozone layer, garnering considerable attention within the scientific community. Consequently, the investigation of Freon degradation has become a central focus of current research efforts. In this study, we opted to employ catalytic hydrolysis as it offers numerous advantages for the degradation of HCFC-22. Specifically, we prepared ZnO/ZrO 2 catalysts with hexahedral rod-like structures through citric acid complexation. We examined the impact of various preparation conditions (such as the molar ratio of ZnO to ZrO 2 , calcination temperature, and calcination time) as well as catalytic hydrolysis conditions (including the amount of catalyst, total flow rate, and catalytic hydrolysis temperature) on the hydrolysis rate of HCFC-22. Characterization of the catalysts was performed using techniques such as XRD, SEM, EDS, TG-DTG, FTIR, N 2 adsorption-desorption, CO 2 -TPD, and NH 3 -TPD. Our experimental findings revealed the optimal preparation conditions: a catalytic hydrolysis temperature of 100 °C, a molar ratio of ZnO to ZrO 2 of 0.7, a water bath temperature of 90 °C, a roasting temperature of 400 °C, and a roasting time of 4 h. At a catalytic hydrolysis temperature of 100 °C, the hydrolysis rate of HCFC-22 reached 99.81%, with the main hydrolyzed products being HCl, HF, and CO 2 ., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Given the increasing investment by Belt and Road Initiative (BRI) participants in the renewable energy industry, it is imperative to ascertain how much this investment contributes to economic growth. The objective of this study is to ascertain the extent to which renewable energy contributes to economic growth within the Belt and Road Initiative compared to non-renewable energy sources. Prior studies have yet to incorporate oil prices as a variable in the production function, among other output aspects. This study integrates the inclusion of real oil prices as a variable within the production function alongside capital, labor, renewable energy consumption, and non-renewable energy consumption. A cohort including 49 Belt and Road Initiative participants was formed, encompassing data from 1990 to 2019. The data has undergone an initial examination to assess cross-sectional dependence, slope heterogeneity, and structural break(s), and are verified. Hence, third-generation panel data analysis has been utilized. The continuously updated fully modified estimator and continuously updated biased corrected estimator provide evidence supporting the notion that renewable energy plays a substantial role in fostering economic growth within nations participating in the Belt and Road Initiative. Furthermore, this contribution is found to be more pronounced when compared to the impact of non-renewable energy sources. The study's findings inform policy recommendations at both the BRI and national level., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

As the urgency to address climate change intensifies, the exploration of sustainable negative emission technologies becomes imperative. Enhanced weathering (EW) represents an approach by leveraging the natural process of rock weathering to sequester atmospheric carbon dioxide (CO 2 ) in agricultural lands. This review synthesizes current research on EW, focusing on its mechanisms, influencing factors, and pathways for successful integration into agricultural practices. It evaluates key factors such as material suitability, particle size, application rates, soil properties, and climate, which are crucial for optimizing EW's efficacy. The study highlights the multifaceted benefits of EW, including soil fertility improvement, pH regulation, and enhanced water retention, which collectively contribute to increased agricultural productivity and climate change mitigation. Furthermore, the review introduces Monitoring, Reporting, and Verification (MRV) and Carbon Dioxide Removal (CDR) verification frameworks as essential components for assessing and enhancing EW's effectiveness and credibility. By examining the current state of research and proposing avenues for future investigation, this review aims to deepen the understanding of EW's role in sustainable agriculture and climate change mitigation strategies., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The Russia-Ukraine war and other similar conflicts across the globe have heightened risks to the United States of America's (USA's) energy security. However, little is known about the severity of the effect of energy security risks on the USA's quest to attain net-zero emissions targets by 2050. To this end, we examine the effect of energy security risks on the load capacity factor (LCF) in the USA. Employing a time series dataset spinning from 1970 to 2018, the results of the Dynamic Autoregressive Distributed Lag (ARDL) simulations model suggest that energy security-related risk hampers the long-term net-zero emissions targets with its effect decreasing over time until it varnishes in about 5 years time. The results also show that foreign direct investment (FDI) inflows, renewable energy consumption, and green technology have long- and short-run positive effects on the LCF. Conversely, economic expansion and urbanization impede environmental quality by lowering the LCF both in the long run and short run. These findings are upheld by the outcomes of the multivariate quantile-on-quantile regression. Therefore, the study advocates for the consumption of renewable energy, investment in green technologies, and FDI inflows to mitigate energy security-related risks and attain the net-zero emissions targets by 2050 in the USA., (© 2024. The Author(s).)

The BRICS countries ratified the 2030 Sustainable Development Goals agenda whereby ensuring environmental sustainability is of paramount importance for these emerging market economies. Although the BRICS nations have recorded noteworthy economic growth trajectories over the last couple of decades, these nations have not fared well in terms of improving their environmental indicators, especially due to gradually becoming more fossil fuel dependent over time. Hence, this study aims to explore whether undergoing the renewable energy transition can directly and indirectly establish environmental sustainability in the BRICS countries by containing their annual growth rates of carbon dioxide emissions. Additionally, the emission growth rate-influencing effects of technological innovation, foreign direct investment receipts, urbanization, and institutional quality are also evaluated. Based on data spanning from 1996 to 2021 and considering the result obtained using advanced panel data estimators, the findings endorse that the yearly carbon emission growth rates are (a) unaffected by undergoing the renewable energy transition on its own; (b) positively impacted by technological innovation, net receipts of foreign direct investment, and urbanization; and (c) negatively impacted by improving institutional quality through effective controlling of the spread of corruption. More importantly, the results verify the joint carbon emission growth rate-mitigating impact of renewable energy transition and institutional quality improvement. Hence, for abating the emission growth rate figures, several policies are prescribed., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Climate change repercussions such as temperature shifts and more severe weather occurrences are felt globally. It contributes to larger-scale challenges, such as climate change and biodiversity loss in food production. As a result, the purpose of this research is to develop strategies to grow the economy without harming the environment. Therefore, we revisit the environmental Kuznets curve (EKC) hypothesis, considering the impact of climate policy uncertainty along with other control variables. We investigated yearly panel data from 47 Belt and Road Initiative (BRI) nations from 1998 to 2021. Pooled regression, fixed effect, and the generalized method of moment (GMM) findings all confirmed the presence of inverted U-shaped EKC in BRI counties. Findings from this paper provide policymakers with actionable ideas, outlining a framework for bringing trade and climate agendas into harmony in BRI countries. The best way to promote economic growth and reduce carbon dioxide emissions is to push for trade and climate policies to be coordinated. Moreover, improving institutional quality is essential for strong environmental governance, as it facilitates the adoption of environmentally friendly industrialization techniques and the efficient administration of climate policy uncertainties., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

China faces the dual pressure of haze pollution control and carbon emission reduction. The goals of national key ecological functional areas (NKEFAs) are to improve ecological quality and enhance ecological supply. In this paper, a time-varying difference-in-differences model is used to assess the impact of NKEFAs on PM 2.5 and CO 2 by the panel data of prefecture-level cities of China and then investigate the synergistic reduction effect. This quasi-natural experiment reveals that NKEFAs can effectively reduce both PM 2.5 and CO 2 and then achieve the synergistic emission reduction effect. Land use pattern optimization and productivity enhancement are identified as key drivers for promoting this synergistic effect. This effect is observed in NKEFAs of water conservation and soil conservation types, as well as in the northern region, middle and lower reaches of the Yangtze River, and southeast coastal areas of the southern region. This study provides valuable theoretical references and empirical insights for realizing a synergistic status of environmental improvement and low-carbon transformation., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A country's financing system is essential in addressing sustainable development requirements. National sources and international financial flows contribute to economic growth and environmental quality in many ways, and their impact can be critical. This paper applied panel data analysis using a comparative approach of Pooled Mean Group Auto Regressive Distribute Lags (PMG-ARDL) and Cross Sectionally ARDL (CS-ARDL) to estimate the effects of FDI, renewable energy, and remittance on environmental quality in the top remittance-receiving countries, during 2000-2021. The study emphasized the positive relationship between FDI and carbon emissions. Moreover, renewable energy and remittances revealed an inverted U-shaped relationship with carbon emissions. In the case of developing countries from the panel, remittance improves environmental quality after reaching the threshold. Moreover, for some of the developing countries included in the panel, we found that they do not achieve the desired carbon mitigation effect in their early stages of renewable energy implementation. However, renewable energy becomes a key factor for tackling environmental pollution after a certain threshold. The mixed results determined diverse policy recommendations for various stakeholders., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)