Logan Cochrane, Dhabia Al Mohannadi, Sa'd Shannak, Yoshihide Wada, Esra Al Eisa, Mohamad Hejazi
Countries in the Arabian Gulf are reliant upon hydrocarbons for revenues, exports, industries and funding services. It is largely assumed that the global energy transition will be gradual, as reflected in planning and strategy documents. However, energy breakthroughs can change the global energy system. This Perspective article seeks to provoke a discussion about potential energy breakthroughs, the plausibility of their rapid expansion at scale, and the implications they may have for the hydrocarbon economies in the Arabian Gulf. Based upon feasibility, scalability, and adoption potential energy breakthroughs are outlined, their probability are assessed, and potential impacts on the hydrocarbon economics of the region are evaluated. The calls to actions are concluded with aim to support the region to be better prepared to track breakthroughs, and be proactively engaged to benefit from them. These include: 1) annual regional research-policy interface meetings, 2) tailored research and development funding that fosters regional collaboration, 3) investment into breakthrough technologies and energy transition inputs, and 4) seeking synergy in economic diversification regionally to avoid duplication and counterproductive competition.
{"title":"Future Energy Breakthroughs: Implications for the Hydrocarbon Economies of the Arabian Gulf","authors":"Logan Cochrane, Dhabia Al Mohannadi, Sa'd Shannak, Yoshihide Wada, Esra Al Eisa, Mohamad Hejazi","doi":"10.1002/gch2.202400151","DOIUrl":"10.1002/gch2.202400151","url":null,"abstract":"<p>Countries in the Arabian Gulf are reliant upon hydrocarbons for revenues, exports, industries and funding services. It is largely assumed that the global energy transition will be gradual, as reflected in planning and strategy documents. However, energy breakthroughs can change the global energy system. This Perspective article seeks to provoke a discussion about potential energy breakthroughs, the plausibility of their rapid expansion at scale, and the implications they may have for the hydrocarbon economies in the Arabian Gulf. Based upon feasibility, scalability, and adoption potential energy breakthroughs are outlined, their probability are assessed, and potential impacts on the hydrocarbon economics of the region are evaluated. The calls to actions are concluded with aim to support the region to be better prepared to track breakthroughs, and be proactively engaged to benefit from them. These include: 1) annual regional research-policy interface meetings, 2) tailored research and development funding that fosters regional collaboration, 3) investment into breakthrough technologies and energy transition inputs, and 4) seeking synergy in economic diversification regionally to avoid duplication and counterproductive competition.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 12","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11637773/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142827765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The main objective of this study is to map and evaluate groundwater potential zones (GWPZs) using advanced ensemble machine learning (ML) models, notably Random Forest (RF) and Support Vector Machine (SVM). GWPZs are identified by considering essential factors such as geology, drainage density, slope, land use/land cover (LULC), rainfall, soil, and lineament density. This is combined with datasets used for training and validating the RF and SVM models, which consisted of 75 potential sites (boreholes and springs), 22 non-potential sites (bare lands and settlement areas), and 20 potential sites (water bodies). Each dataset is randomly partitioned into two sets: training (70%) and validation (30%). The model's performance is evaluated using the area under the receiver operating characteristic curve (AUC-ROC). The AUC of the RF model is 0.91, compared to 0.88 for the SVM model. Both models classified GWPZs effectively, but the RF model performed slightly better. The classified GWPZ map shows that high GWPZs are typically located within water bodies, natural springs, low-lying regions, and forested areas. In contrast, low GWPZs are primarily found in shrubland and grassland areas. This study is vital for decision-makers as it promotes sustainable groundwater use and ensures water security in the studied area.
{"title":"Evaluation of Groundwater Potential Zones Using GIS-Based Machine Learning Ensemble Models in the Gidabo Watershed, Ethiopia","authors":"Mussa Muhaba Mussa, Tarun Kumar Lohani, Abunu Atlabachew Eshete","doi":"10.1002/gch2.202400137","DOIUrl":"10.1002/gch2.202400137","url":null,"abstract":"<p>The main objective of this study is to map and evaluate groundwater potential zones (GWPZs) using advanced ensemble machine learning (ML) models, notably Random Forest (RF) and Support Vector Machine (SVM). GWPZs are identified by considering essential factors such as geology, drainage density, slope, land use/land cover (LULC), rainfall, soil, and lineament density. This is combined with datasets used for training and validating the RF and SVM models, which consisted of 75 potential sites (boreholes and springs), 22 non-potential sites (bare lands and settlement areas), and 20 potential sites (water bodies). Each dataset is randomly partitioned into two sets: training (70%) and validation (30%). The model's performance is evaluated using the area under the receiver operating characteristic curve (AUC-ROC). The AUC of the RF model is 0.91, compared to 0.88 for the SVM model. Both models classified GWPZs effectively, but the RF model performed slightly better. The classified GWPZ map shows that high GWPZs are typically located within water bodies, natural springs, low-lying regions, and forested areas. In contrast, low GWPZs are primarily found in shrubland and grassland areas. This study is vital for decision-makers as it promotes sustainable groundwater use and ensures water security in the studied area.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 12","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11637779/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142827637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Sathish, Jayant Giri, R. Saravanan, Ümit Ağbulut
Animal flesh is a major food source with economic and industrial value for consumer demand. These meats produced biowaste during and after preparation and use. Chicken intestines make up most of the waste thrown away after processing or frying. This study considers it a biodiesel source. Transesterification turns chicken intestine waste fat oil into biodiesel. This oil is used in compression ignition (CI) engines but performs poorly compared to diesel. Diesel, the base fuel, is mixed with 20% biodiesel. The remaining 10% and 20% of butanol and pentanol are port fuels, improving combustion and lowering emissions in the 5.2 kW, 1500 rpm CI engine. 20% pentanol premixing outperformed butanol premixing, blending, and engine CIWFOB operation. The greater heating value improves combustion, therefore 20% pentanol premixing with blend produces 32.76% BTE, 10.57% more than diesel. It produced 55.18% less CO and 50.92% less smoke than diesel, which has a greater heat release rate (48.86 J/CAD) and peak pressure (64.76 bar). This premixing costs NOx emissions. The CIWFOB blend with 20% pentanol premixing improves engine performance. For SDGs 7, 9, 12, and 13, this study is supported.
{"title":"Waste to Energy: Combustion, Performance, and Emission Characteristics of Waste Animal Fats/Diesel Blends Premixed with Various Alcohols as Port Fuels","authors":"T. Sathish, Jayant Giri, R. Saravanan, Ümit Ağbulut","doi":"10.1002/gch2.202400189","DOIUrl":"10.1002/gch2.202400189","url":null,"abstract":"<p>Animal flesh is a major food source with economic and industrial value for consumer demand. These meats produced biowaste during and after preparation and use. Chicken intestines make up most of the waste thrown away after processing or frying. This study considers it a biodiesel source. Transesterification turns chicken intestine waste fat oil into biodiesel. This oil is used in compression ignition (CI) engines but performs poorly compared to diesel. Diesel, the base fuel, is mixed with 20% biodiesel. The remaining 10% and 20% of butanol and pentanol are port fuels, improving combustion and lowering emissions in the 5.2 kW, 1500 rpm CI engine. 20% pentanol premixing outperformed butanol premixing, blending, and engine CIWFOB operation. The greater heating value improves combustion, therefore 20% pentanol premixing with blend produces 32.76% BTE, 10.57% more than diesel. It produced 55.18% less CO and 50.92% less smoke than diesel, which has a greater heat release rate (48.86 J/CAD) and peak pressure (64.76 bar). This premixing costs NOx emissions. The CIWFOB blend with 20% pentanol premixing improves engine performance. For SDGs 7, 9, 12, and 13, this study is supported.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 12","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11637774/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142828172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study explains the time-quantile-frequency adjustments of green growth to energy vulnerability, energy uncertainties, and geopolitical risks (GPR) in the United States (US). Novel insights with notable policy implications emerged following the empirical analysis of monthly data spanning 2000 m1–2022 m12. The study implemented the Wavelet Quantile Correlation (WQC), Wavelet Quantile Granger Causality, and the Rolling Windows Wavelet Quantile Granger Causality to understand the dynamics among the variables. Evidence from WQC divulged time-specific positive and negative interactions between green growth and its determinants. Specifically, energy vulnerability dampened green growth more profoundly in the immediate and medium terms. However, in the long term, green growth prospers amidst energy vulnerability. This outcome reflects some policy effectiveness that reduced the negative effects of energy vulnerability for green growth. The effects of energy uncertainties are similar to that of energy vulnerability, with more profound damaging effects in the lower medium horizon of the distributions. GPR dampened green growth in the short run and enhanced it in the medium term, but it reduced green growth more profoundly in the long run. The pleasant effects of energy efficiency and digitalization are observed mostly in the long run, with notable green growth-reducing effects mainly in the short run.
{"title":"Time-Quantile and Frequency Response of Green Growth to Energy Vulnerability, Energy Uncertainty, and Geopolitical Risks","authors":"Emmanuel Uche","doi":"10.1002/gch2.202400225","DOIUrl":"10.1002/gch2.202400225","url":null,"abstract":"<p>The study explains the time-quantile-frequency adjustments of green growth to energy vulnerability, energy uncertainties, and geopolitical risks (GPR) in the United States (US). Novel insights with notable policy implications emerged following the empirical analysis of monthly data spanning 2000 m1–2022 m12. The study implemented the Wavelet Quantile Correlation (WQC), Wavelet Quantile Granger Causality, and the Rolling Windows Wavelet Quantile Granger Causality to understand the dynamics among the variables. Evidence from WQC divulged time-specific positive and negative interactions between green growth and its determinants. Specifically, energy vulnerability dampened green growth more profoundly in the immediate and medium terms. However, in the long term, green growth prospers amidst energy vulnerability. This outcome reflects some policy effectiveness that reduced the negative effects of energy vulnerability for green growth. The effects of energy uncertainties are similar to that of energy vulnerability, with more profound damaging effects in the lower medium horizon of the distributions. GPR dampened green growth in the short run and enhanced it in the medium term, but it reduced green growth more profoundly in the long run. The pleasant effects of energy efficiency and digitalization are observed mostly in the long run, with notable green growth-reducing effects mainly in the short run.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 12","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11637780/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142828170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yizhan Wu, Fei Guo, Yan Ma, Weihao Chai, Jiajia Li, Wenhui Shi, Jiangwei Liu
Heatstroke (HS) is a severe systemic condition that significantly impacts organ function, with the liver being particularly vulnerable. Sirtuin 1 (SIRT1), a crucial deacetylase, is implicated in various diseases' pathophysiology. Curcumin, a natural polyphenol, has been shown to modulate SIRT1 activity, offering therapeutic benefits. This study explores the impact of HS on hepatic SIRT1 expression and the protective mechanisms of curcumin against HS-induced hepatic injury. Male C57BL/6 mice are divided into control and curcumin pretreatment groups, subjected to HS induction, and assessed for liver injury biomarkers, oxidative stress, and inflammatory cytokines. Results indicate that HS downregulates SIRT1, leading to liver damage and systemic inflammation. Curcumin pretreatment dose-responsively attenuates these effects, with the highest dose providing optimal protection, potentially through SIRT1 restoration. The findings suggest that curcumin's hepatoprotective role in HS may be mediated by upregulating SIRT1, highlighting its therapeutic potential in heatstroke-related liver damage.
{"title":"Curcumin's Protective Role in Heatstroke-Induced Acute Liver Injury: Targeting Pyroptosis and Enhancing SIRT1 Expression","authors":"Yizhan Wu, Fei Guo, Yan Ma, Weihao Chai, Jiajia Li, Wenhui Shi, Jiangwei Liu","doi":"10.1002/gch2.202400178","DOIUrl":"10.1002/gch2.202400178","url":null,"abstract":"<p>Heatstroke (HS) is a severe systemic condition that significantly impacts organ function, with the liver being particularly vulnerable. Sirtuin 1 (SIRT1), a crucial deacetylase, is implicated in various diseases' pathophysiology. Curcumin, a natural polyphenol, has been shown to modulate SIRT1 activity, offering therapeutic benefits. This study explores the impact of HS on hepatic SIRT1 expression and the protective mechanisms of curcumin against HS-induced hepatic injury. Male C57BL/6 mice are divided into control and curcumin pretreatment groups, subjected to HS induction, and assessed for liver injury biomarkers, oxidative stress, and inflammatory cytokines. Results indicate that HS downregulates SIRT1, leading to liver damage and systemic inflammation. Curcumin pretreatment dose-responsively attenuates these effects, with the highest dose providing optimal protection, potentially through SIRT1 restoration. The findings suggest that curcumin's hepatoprotective role in HS may be mediated by upregulating SIRT1, highlighting its therapeutic potential in heatstroke-related liver damage.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 12","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11637775/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142827635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A M Almas Shahriyar Azad, Zarin Tasnim Oishi, Md. Ariful Islam, Md. Rakibul Islam
The design of renewable energy systems traditionally emphasizes life cycle costs, often focusing primarily on emissions rather than a comprehensive life cycle impact assessment. This research proposes a four-tier methodology to balance cost-effectiveness and sustainability in the electrification of remote areas. Tier 1 focuses on understanding the community context by analyzing electrical load profiles, meteorological data, and component specifications for microgrid design. Tier 2 evaluates the feasibility of various systems, optimizing them through cost analysis and Multi-Criteria Decision-Making (MCDM) to rank alternatives. Tier 3 assesses environmental impacts using life cycle assessment, ranking alternatives based on environmental criteria. Tier 4 integrates cost and environmental rankings to determine the most suitable energy configurations, followed by sensitivity analysis to ensure robust decision-making. The methodology is validated through a case study of an unelectrified remote community, demonstrating that the PV-Wind Turbine-Biomass Generator-Converter configuration is the most robust alternative, proving to be the optimal choice in 50% of the analyzed scenarios, achieving a Cost of Energy of 0.213 USD/kWh while minimizing environmental impact across all 18 criteria considered over a 25-year life cycle. This novel framework offers a scalable approach to designing renewable energy systems, enhancing sustainable electrification efforts in developing regions.
{"title":"Advancing Economical and Environmentally Conscious Electrification: A Comprehensive Framework for Microgrid Design in Off-Grid Regions","authors":"A M Almas Shahriyar Azad, Zarin Tasnim Oishi, Md. Ariful Islam, Md. Rakibul Islam","doi":"10.1002/gch2.202400169","DOIUrl":"https://doi.org/10.1002/gch2.202400169","url":null,"abstract":"<p>The design of renewable energy systems traditionally emphasizes life cycle costs, often focusing primarily on emissions rather than a comprehensive life cycle impact assessment. This research proposes a four-tier methodology to balance cost-effectiveness and sustainability in the electrification of remote areas. Tier 1 focuses on understanding the community context by analyzing electrical load profiles, meteorological data, and component specifications for microgrid design. Tier 2 evaluates the feasibility of various systems, optimizing them through cost analysis and Multi-Criteria Decision-Making (MCDM) to rank alternatives. Tier 3 assesses environmental impacts using life cycle assessment, ranking alternatives based on environmental criteria. Tier 4 integrates cost and environmental rankings to determine the most suitable energy configurations, followed by sensitivity analysis to ensure robust decision-making. The methodology is validated through a case study of an unelectrified remote community, demonstrating that the PV-Wind Turbine-Biomass Generator-Converter configuration is the most robust alternative, proving to be the optimal choice in 50% of the analyzed scenarios, achieving a Cost of Energy of 0.213 USD/kWh while minimizing environmental impact across all 18 criteria considered over a 25-year life cycle. This novel framework offers a scalable approach to designing renewable energy systems, enhancing sustainable electrification efforts in developing regions.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 11","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/gch2.202400169","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Photocatalytic water splitting is an environmentally friendly hydrogen production method that uses abundant renewable resources such as water and sunlight. While Titanium dioxide (TiO2) photocatalyst exhibits excellent properties, its high band gap limits absorption to ultraviolet (UV) irradiation, resulting in low photo conversion efficiency. This review explores various modification techniques aimed at enhancing the efficiency of TiO2 under visible light irradiation. Factors influencing the photocatalytic water splitting reaction, such as catalyst structure, morphology, band gap, sacrificial reagents, light intensity, temperature, and potential of Hydrogen (pH) are examined. This review also summarizes different catalyst synthesis methods, and types of photocatalytic reactors, and provides insights into quantum yield. Finally, the review addresses the challenges and future outlook of photocatalytic water splitting.
{"title":"Photocatalytic Hydrogen Production Using TiO2-based Catalysts: A Review","authors":"Fahima Bhom, Yusuf Makarfi Isa","doi":"10.1002/gch2.202400134","DOIUrl":"10.1002/gch2.202400134","url":null,"abstract":"<p>Photocatalytic water splitting is an environmentally friendly hydrogen production method that uses abundant renewable resources such as water and sunlight. While Titanium dioxide (TiO<sub>2</sub>) photocatalyst exhibits excellent properties, its high band gap limits absorption to ultraviolet (UV) irradiation, resulting in low photo conversion efficiency. This review explores various modification techniques aimed at enhancing the efficiency of TiO<sub>2</sub> under visible light irradiation. Factors influencing the photocatalytic water splitting reaction, such as catalyst structure, morphology, band gap, sacrificial reagents, light intensity, temperature, and potential of Hydrogen (pH) are examined. This review also summarizes different catalyst synthesis methods, and types of photocatalytic reactors, and provides insights into quantum yield. Finally, the review addresses the challenges and future outlook of photocatalytic water splitting.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 11","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11557513/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142618583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Przemysław Strachowski, Geeta Mandava, Johan Lundqvist, Romain Bordes, Mehdi Abdollahi
A novel approach for reducing mercury content in fish meat during post-packaging storage is developed to extend the margin of their safe consumption. It involves employing a single-component aqueous medium containing cysteine, as the active agent responsible for displacing mercury from fish proteins and its stabilization in the medium without the need for pH adjustments. The mercury removal efficiency depends on the cysteine concentration and its ratio to fish muscle. Using 1.2 wt% cysteine enables a reduction of mercury in canned Albacore tuna by 25–35%, depending on the fish product type and the exposure time of up to 2 weeks. The potential for the successful application of the developed method in active food packaging solutions is studied for the simultaneous or subsequent purification of the extraction solution through adsorption. Using thiolated silica could potentially enable the extraction process but it is shown that the presence of cysteine significantly hinders the adsorption.
{"title":"New Insight into Mercury Removal from Fish Meat Using a Single-Component Solution Containing cysteine","authors":"Przemysław Strachowski, Geeta Mandava, Johan Lundqvist, Romain Bordes, Mehdi Abdollahi","doi":"10.1002/gch2.202400161","DOIUrl":"10.1002/gch2.202400161","url":null,"abstract":"<p>A novel approach for reducing mercury content in fish meat during post-packaging storage is developed to extend the margin of their safe consumption. It involves employing a single-component aqueous medium containing cysteine, as the active agent responsible for displacing mercury from fish proteins and its stabilization in the medium without the need for pH adjustments. The mercury removal efficiency depends on the cysteine concentration and its ratio to fish muscle. Using 1.2 wt% cysteine enables a reduction of mercury in canned Albacore tuna by 25–35%, depending on the fish product type and the exposure time of up to 2 weeks. The potential for the successful application of the developed method in active food packaging solutions is studied for the simultaneous or subsequent purification of the extraction solution through adsorption. Using thiolated silica could potentially enable the extraction process but it is shown that the presence of cysteine significantly hinders the adsorption.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 11","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11557507/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142618582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kaisar Ahmad, Aasif Asharafbhai Dabbawala, Kyriaki Polychronopoulou, Dalaver Anjum, Marko Gacesa, Maguy Abi Jaoude
This study presents a single-site microkinetic model for methanol synthesis by CO2 hydrogenation over intermetallic Pd2Ga/SiO2. A reaction path analysis (RPA) combining theoretical results and realistic catalyst surface reaction data is established to elucidate the reaction mechanism and kinetic models of CO2 hydrogenation to methanol and CO. The RPA leads to the derivation of rate expressions for both reactions without presumptions about the most abundant reactive intermediate (MARI) and rate-determining step (rds). The formation of H2COOH* is found to be the rds (step 19) for methanol synthesis via the formate pathway, with CO2 and H-atoms adsorbed on intermetallic sites as the MARIs. The derived kinetic model is corroborated with experimental data acquired under different reaction conditions, using a lab-scale fixed-bed reactor and Pd2Ga/SiO2 nanoparticles prepared by incipient wetness impregnation. The excellent agreement between the experimental data and the kinetic model (R2 = 0.99) substantiates the proposed mechanism with an activation energy of 61.52 kJ mol-1 for methanol synthesis. The reported catalyst exhibits high selectivity to methanol (96%) at 1 bar, 150 °C, and H2/CO2 ratio of 3:1. These findings provide critical insights to optimize catalysts and processes targeting CO2 hydrogenation at atmospheric pressure and low temperatures for on-demand energy production.
本研究提出了在金属间 Pd2Ga/SiO2 上通过 CO2 加氢合成甲醇的单位微动力学模型。结合理论结果和实际催化剂表面反应数据,建立了反应路径分析(RPA),以阐明 CO2 加氢生成甲醇和 CO 的反应机理和动力学模型。通过 RPA,可以推导出这两个反应的速率表达式,而无需假定最丰富的反应中间体(MARI)和速率决定步骤(rds)。发现 H2COOH* 的形成是通过甲酸途径合成甲醇的速率决定步骤(步骤 19),金属间位点上吸附的 CO2 和 H 原子为 MARI。利用实验室规模的固定床反应器和通过初湿浸渍法制备的 Pd2Ga/SiO2 纳米粒子,在不同反应条件下获得的实验数据证实了推导出的动力学模型。实验数据与动力学模型(R2 = 0.99)之间的极佳一致性证实了所提出的机制,即甲醇合成的活化能为 61.52 kJ mol-1。在 1 bar、150 °C 和 H2/CO2 比率为 3:1 的条件下,报告的催化剂对甲醇具有很高的选择性(96%)。这些发现为优化常压低温下二氧化碳加氢催化剂和工艺以按需生产能源提供了重要启示。
{"title":"Kinetic Insights into Methanol Synthesis from CO2 Hydrogenation at Atmospheric Pressure over Intermetallic Pd2Ga Catalyst","authors":"Kaisar Ahmad, Aasif Asharafbhai Dabbawala, Kyriaki Polychronopoulou, Dalaver Anjum, Marko Gacesa, Maguy Abi Jaoude","doi":"10.1002/gch2.202400159","DOIUrl":"https://doi.org/10.1002/gch2.202400159","url":null,"abstract":"<p>This study presents a single-site microkinetic model for methanol synthesis by CO<sub>2</sub> hydrogenation over intermetallic Pd<sub>2</sub>Ga/SiO<sub>2</sub>. A reaction path analysis (RPA) combining theoretical results and realistic catalyst surface reaction data is established to elucidate the reaction mechanism and kinetic models of CO<sub>2</sub> hydrogenation to methanol and CO. The RPA leads to the derivation of rate expressions for both reactions without presumptions about the most abundant reactive intermediate (MARI) and rate-determining step (rds). The formation of H<sub>2</sub>COOH* is found to be the rds (step 19) for methanol synthesis via the formate pathway, with CO<sub>2</sub> and H-atoms adsorbed on intermetallic sites as the MARIs. The derived kinetic model is corroborated with experimental data acquired under different reaction conditions, using a lab-scale fixed-bed reactor and Pd<sub>2</sub>Ga/SiO<sub>2</sub> nanoparticles prepared by incipient wetness impregnation. The excellent agreement between the experimental data and the kinetic model (<i>R</i><sup>2</sup> = 0.99) substantiates the proposed mechanism with an activation energy of 61.52 kJ mol<sup>-1</sup> for methanol synthesis. The reported catalyst exhibits high selectivity to methanol (96%) at 1 bar, 150 °C, and H<sub>2</sub>/CO<sub>2</sub> ratio of 3:1. These findings provide critical insights to optimize catalysts and processes targeting CO<sub>2</sub> hydrogenation at atmospheric pressure and low temperatures for on-demand energy production.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 10","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/gch2.202400159","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142430125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Visible-light active anatase/brookite/rutile (A/B/R) ternary N-doped titania (N/TiO2) crystals are successfully prepared by a facile sol-gel method using titanium butoxide and benign N-dopant source, guanidinium chloride. Systematically varying the aging time (1, 4, 8, and 12 d), its influence on physicochemical properties of as-obtained spherical heterojunction nanomaterials is studied. Detailed characterizations confirm that a substantial amount of anatase (88% to 50%) is transformed to rutile (2% to 38%) via intermediate brookite phase (9% to 25%) as the function of aging time; not only the A/B/R phase content of the samples is tuned by sol-gel aging time of the precursors solution but also their optical-response and methylene blue photocatalytic properties are profoundly dictated. Notably under visible-light irradiation, the photostable rutile rich mesoporous A/B/R triphasic N/TiO2 (50% A, 12% B, 38% R) aged for 12 d demonstrates higher degradation activity (97%) with a faster degradation rate (0.033 min−1) than both lesser aged N/TiO2 and undoped titania. This enhancement is attributed to the synergistic effect of interstitial-N-doping and optimal A/B/R interfacial charge transfer that leads to higher light absorption, lower bandgap energy and well-separated charge carriers. The current work provides a new perspective for designing highly active visible-light heterostructure nanomaterials with controllable phase composition.
利用丁氧化钛和良性 N 掺杂源氯化胍,通过简便的溶胶-凝胶法成功制备了具有可见光活性的锐钛矿/闪长岩/金红石(A/B/R)三元 N 掺杂二氧化钛(N/TiO2)晶体。研究人员系统地改变了老化时间(1、4、8 和 12 d),研究了老化时间对球形异质结纳米材料物理化学性质的影响。详细的表征结果证实,随着老化时间的延长,大量锐钛矿相(88%-50%)通过中间褐铁矿相(9%-25%)转变为金红石相(2%-38%);前驱体溶液的溶胶-凝胶老化时间不仅调节了样品中 A/B/R 相的含量,还极大地影响了它们的光学响应和亚甲基蓝光催化特性。值得注意的是,在可见光辐照下,与老化时间较短的 N/TiO2 和未掺杂的二氧化钛相比,老化 12 d 的富金红石介孔 A/B/R 三相 N/TiO2 (50% A、12% B、38% R)具有更高的降解活性(97%)和更快的降解速率(0.033 min-1)。这种增强归因于间隙-N掺杂和最佳A/B/R界面电荷转移的协同效应,从而导致更高的光吸收、更低的带隙能和良好的电荷载流子分离。目前的研究为设计具有可控相组成的高活性可见光异质结构纳米材料提供了新的视角。
{"title":"In Situ Driven Formation of Anatase/Brookite/Rutile Heterojunction N/TiO2 Nanocrystals as Sustainable Visible-Light Catalysts","authors":"Elias Assayehegn, Ananthakumar Solaiappan, Abraha Tadese Gidey, Gebremedhin Gebremariam Gebreegziabher, Tesfamariam Teklu Gebretsadik, Yonas Chebude, Esayas Alemayehu","doi":"10.1002/gch2.202400174","DOIUrl":"https://doi.org/10.1002/gch2.202400174","url":null,"abstract":"<p>Visible-light active anatase/brookite/rutile (A/B/R) ternary N-doped titania (N/TiO<sub>2</sub>) crystals are successfully prepared by a facile sol-gel method using titanium butoxide and benign N-dopant source, guanidinium chloride. Systematically varying the aging time (1, 4, 8, and 12 d), its influence on physicochemical properties of as-obtained spherical heterojunction nanomaterials is studied. Detailed characterizations confirm that a substantial amount of anatase (88% to 50%) is transformed to rutile (2% to 38%) via intermediate brookite phase (9% to 25%) as the function of aging time; not only the A/B/R phase content of the samples is tuned by sol-gel aging time of the precursors solution but also their optical-response and methylene blue photocatalytic properties are profoundly dictated. Notably under visible-light irradiation, the photostable rutile rich mesoporous A/B/R triphasic N/TiO<sub>2</sub> (50% A, 12% B, 38% R) aged for 12 d demonstrates higher degradation activity (97%) with a faster degradation rate (0.033 min<sup>−1</sup>) than both lesser aged N/TiO<sub>2</sub> and undoped titania. This enhancement is attributed to the synergistic effect of interstitial-N-doping and optimal A/B/R interfacial charge transfer that leads to higher light absorption, lower bandgap energy and well-separated charge carriers. The current work provides a new perspective for designing highly active visible-light heterostructure nanomaterials with controllable phase composition.</p>","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"8 10","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/gch2.202400174","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142430147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}