Journal of The Energy Institute最新文献

The migration and transformation mechanism of N in ammonia/coal volatile co-combustion: Experimental and quantum chemical calculation

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-09 DOI: 10.1016/j.joei.2025.102091

Ping Chen , Longxiang Qiao , Xiang Li , Mingyan Gu , Kun Luo , Xun Hu

It is very important to understand the NO formation characteristics and N conversion mechanism of ammonia/coal volatile combustion for low nitrogen combustion during ammonia-coal co-combustion. In this work, constant temperature furnace experiment and quantum chemistry calculation were used to study the migration and transformation characteristics of N for ammonia/coal volatile co-combustion. The experimental results showed that the ammonia blending ratio and temperature have significant effects on the formation of NO in volatile combustion. When the ammonia ratio was less than 10 %, volatile combustion preceded ammonia combustion, and unburned ammonia reduced part of NO at high temperature, so that the stable concentration of NO in ammonia/volatile combustion increased first and then decreased with the temperature increasing. The combustion performance of ammonia was enhanced with the further increase of ammonia blending ratio, and the stable concentration of NO in ammonia/volatile combustion gradually increased with the temperature increasing. The theoretical calculation showed that the ammonia/volatile co-combustion system firstly oxidized ammonia-N, and then oxidized C and N in the volatile. The addition of ammonia reduced the rate-limiting step barrier value of volatile-N oxidation about 53.11 kJ/mol or 99.11 kJ/mol, and promoted the formation of N-containing oxidation products in co-combustion system. The kinetic results showed that the rate-limiting step reaction rate of ammonia/volatile co-combustion system was about 2–4 orders of magnitude higher than that of pure volatile oxidation, and the formation rate of NO gradually increased with the increase of temperature. The theoretical calculation confirmed the experimental phenomenon and revealed the molecular mechanism of N conversion in ammonia/volatile combustion system.

{"title":"The migration and transformation mechanism of N in ammonia/coal volatile co-combustion: Experimental and quantum chemical calculation","authors":"Ping Chen , Longxiang Qiao , Xiang Li , Mingyan Gu , Kun Luo , Xun Hu","doi":"10.1016/j.joei.2025.102091","DOIUrl":"10.1016/j.joei.2025.102091","url":null,"abstract":"<div><div>It is very important to understand the NO formation characteristics and N conversion mechanism of ammonia/coal volatile combustion for low nitrogen combustion during ammonia-coal co-combustion. In this work, constant temperature furnace experiment and quantum chemistry calculation were used to study the migration and transformation characteristics of N for ammonia/coal volatile co-combustion. The experimental results showed that the ammonia blending ratio and temperature have significant effects on the formation of NO in volatile combustion. When the ammonia ratio was less than 10 %, volatile combustion preceded ammonia combustion, and unburned ammonia reduced part of NO at high temperature, so that the stable concentration of NO in ammonia/volatile combustion increased first and then decreased with the temperature increasing. The combustion performance of ammonia was enhanced with the further increase of ammonia blending ratio, and the stable concentration of NO in ammonia/volatile combustion gradually increased with the temperature increasing. The theoretical calculation showed that the ammonia/volatile co-combustion system firstly oxidized ammonia-N, and then oxidized C and N in the volatile. The addition of ammonia reduced the rate-limiting step barrier value of volatile-N oxidation about 53.11 kJ/mol or 99.11 kJ/mol, and promoted the formation of N-containing oxidation products in co-combustion system. The kinetic results showed that the rate-limiting step reaction rate of ammonia/volatile co-combustion system was about 2–4 orders of magnitude higher than that of pure volatile oxidation, and the formation rate of NO gradually increased with the increase of temperature. The theoretical calculation confirmed the experimental phenomenon and revealed the molecular mechanism of N conversion in ammonia/volatile combustion system.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"120 ","pages":"Article 102091"},"PeriodicalIF":5.6,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on the reaction mechanism for hydrogen production from rice straw gasification in supercritical water based on ReaxFF

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-08 DOI: 10.1016/j.joei.2025.102097

Liang Wu , Shenghui Rao , Lihu Zhong , Runqiu Dong , Zhiyong Peng , Le Wang , Lei Yi , Zhigang Liu , Bin Chen

Supercritical Water Gasification (SCWG) is an efficient technology for converting biomass waste into hydrogen-rich gas. In this study, we investigated the gasification process of rice straw under SCW conditions using ReaxFF reactive force field molecular dynamics (MD) simulations combined with experimental validation. The effects of temperature, reactant concentration, and reaction time on gasification efficiency were explored. The results show that under conditions of 4500 K, 3 wt%, and 500 ps, the gasification rate reaches its optimum, with the selectivity proportion of three gases comprising approximately 70 % of the total gas yield. Furthermore, we focused on the radical reactions of water in SCW and the decomposition pathways of cellulose and hemicellulose. Radicals (such as H, OH, and H₃O⁺) generated from water under supercritical conditions drive hydrogen production through dynamic equilibrium reactions. In the reaction pathway, hemicellulose, cellulose, and lignin in rice straw are first hydrolyzed into small molecular monomers, which subsequently undergo dehydrogenation, deoxygenation, ring-opening, and free radical reactions to produce hydrogen and other gaseous products. This study not only provides in-depth insights into the reaction mechanisms of rice straw during SCWG but also offers theoretical guidance for optimizing SCWG systems and advancing their industrial applications.

{"title":"Study on the reaction mechanism for hydrogen production from rice straw gasification in supercritical water based on ReaxFF","authors":"Liang Wu , Shenghui Rao , Lihu Zhong , Runqiu Dong , Zhiyong Peng , Le Wang , Lei Yi , Zhigang Liu , Bin Chen","doi":"10.1016/j.joei.2025.102097","DOIUrl":"10.1016/j.joei.2025.102097","url":null,"abstract":"<div><div>Supercritical Water Gasification (SCWG) is an efficient technology for converting biomass waste into hydrogen-rich gas. In this study, we investigated the gasification process of rice straw under SCW conditions using ReaxFF reactive force field molecular dynamics (MD) simulations combined with experimental validation. The effects of temperature, reactant concentration, and reaction time on gasification efficiency were explored. The results show that under conditions of 4500 K, 3 wt%, and 500 ps, the gasification rate reaches its optimum, with the selectivity proportion of three gases comprising approximately 70 % of the total gas yield. Furthermore, we focused on the radical reactions of water in SCW and the decomposition pathways of cellulose and hemicellulose. Radicals (such as H, OH, and H<sub>3</sub>O<sup>+</sup>) generated from water under supercritical conditions drive hydrogen production through dynamic equilibrium reactions. In the reaction pathway, hemicellulose, cellulose, and lignin in rice straw are first hydrolyzed into small molecular monomers, which subsequently undergo dehydrogenation, deoxygenation, ring-opening, and free radical reactions to produce hydrogen and other gaseous products. This study not only provides in-depth insights into the reaction mechanisms of rice straw during SCWG but also offers theoretical guidance for optimizing SCWG systems and advancing their industrial applications.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"120 ","pages":"Article 102097"},"PeriodicalIF":5.6,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143807790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Superior ZnO-tolerant ability of the CeOx-WO3 mixed oxide catalysts for the selective catalytic reduction of NOx with NH3

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-08 DOI: 10.1016/j.joei.2025.102096

Dong Ye , Yifeng Xu , Jingyi Feng , Xiaoxiang Wang , Li Sun , Kai Zhu , Ruitang Guo

This article demonstrates the superior ZnO tolerance of the CeO_x-WO₃ (CeW) mixed oxide, using the commercialized V₂O₅-WO₃/TiO₂ (VW/Ti) catalyst as a reference. Both fresh CeW and VW/Ti catalysts exhibited >90 % NO_x conversion at temperatures above 300 °C. However, Upon ZnO introduction, the NO_x conversion of both catalysts displayed a declining trend. Notably, at a ZnO loading of 7 wt%, the CeW catalyst maintained >80 % NO_x conversion, while the VW/Ti catalyst showed nearly 0 % NO_x elimination under the same conditions. Characterizations results revealed that loading 3 wt% resulted in a 79 % loss of acid sites on the VW/Ti catalyst. This significant reduction in acidity hindered NH₃ utilization for NO_x reduction, overweighing the positive effects of enhanced NH₃ activation through improved oxidative capacity. Additionally, NO_x adsorption on the ZnO-poisoned catalyst surface formed inert nitrate species, which covered active sites, thereby explaining the severe ZnO-induced deactivation of the VW/Ti composite. In contrast, the ZnO-poisoned CeW catalyst retained moderate acidity, preserving 79 % of its acid sites for NH₃ adsorption. This substantial retention of acid sites ensured the effective progression of NO_x elimination reactions, accounting for the satisfactory ZnO resistance of the CeW catalyst. These finding provide valuable insights for addressing the challenge of stable catalyst operation under ZnO-rich conditions.

{"title":"Superior ZnO-tolerant ability of the CeOx-WO3 mixed oxide catalysts for the selective catalytic reduction of NOx with NH3","authors":"Dong Ye , Yifeng Xu , Jingyi Feng , Xiaoxiang Wang , Li Sun , Kai Zhu , Ruitang Guo","doi":"10.1016/j.joei.2025.102096","DOIUrl":"10.1016/j.joei.2025.102096","url":null,"abstract":"<div><div>This article demonstrates the superior ZnO tolerance of the CeO<sub><em>x</em></sub>-WO<sub>3</sub> (CeW) mixed oxide, using the commercialized V<sub>2</sub>O<sub>5</sub>-WO<sub>3</sub>/TiO<sub>2</sub> (VW/Ti) catalyst as a reference. Both fresh CeW and VW/Ti catalysts exhibited >90 % NO<sub><em>x</em></sub> conversion at temperatures above 300 °C. However, Upon ZnO introduction, the NO<sub><em>x</em></sub> conversion of both catalysts displayed a declining trend. Notably, at a ZnO loading of 7 wt%, the CeW catalyst maintained >80 % NO<sub><em>x</em></sub> conversion, while the VW/Ti catalyst showed nearly 0 % NO<sub><em>x</em></sub> elimination under the same conditions. Characterizations results revealed that loading 3 wt% resulted in a 79 % loss of acid sites on the VW/Ti catalyst. This significant reduction in acidity hindered NH<sub>3</sub> utilization for NO<sub><em>x</em></sub> reduction, overweighing the positive effects of enhanced NH<sub>3</sub> activation through improved oxidative capacity. Additionally, NO<sub><em>x</em></sub> adsorption on the ZnO-poisoned catalyst surface formed inert nitrate species, which covered active sites, thereby explaining the severe ZnO-induced deactivation of the VW/Ti composite. In contrast, the ZnO-poisoned CeW catalyst retained moderate acidity, preserving 79 % of its acid sites for NH<sub>3</sub> adsorption. This substantial retention of acid sites ensured the effective progression of NO<sub><em>x</em></sub> elimination reactions, accounting for the satisfactory ZnO resistance of the CeW catalyst. These finding provide valuable insights for addressing the challenge of stable catalyst operation under ZnO-rich conditions.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"120 ","pages":"Article 102096"},"PeriodicalIF":5.6,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Thermal decomposition kinetics of dairy manure hydrochars

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-07 DOI: 10.1016/j.joei.2025.102088

Kalidas Mainali , Majher I. Sarker , Charles A. Mullen , Brajendra K. Sharma , Madhav P. Yadav , Helen Ngo , Manuel Garcia-Perez

Hydrothermal processes, as well as hydrothermal carbonization (HTC), have emerged as a promising technology for the conversion of high-moisture feedstocks. A total of six hydrochars were generated from dairy manure via H3PO4-catalyzed HTC at varying reaction temperatures and residence times. The heating value of hydrochars produced using HTC (25.64 MJ/kg) has improved significantly from raw dairy manure (17.16 MJ/kg). The kinetic parameters for the thermal decomposition of the manure and its hydrochars were estimated using the Friedman mathematical model. In a comparison of three reaction atmospheres (CO₂, N₂, and air), it was observed that lower activation energies were required in air environments for all specified hydrochars relative to the raw manure. Furthermore, Py-GC-MS studies revealed that light-oxygenated compounds were produced at 500 °C from the hydrochars upon flash pyrolysis. The acid treatment under autogenous pressure, significantly improved manure hydrochars physiochemical properties. The comprehensive theoretical and practical guidelines presented in this study for acid-promoted manure hydrochars indicate that dairy manure can be converted into a substitute energy source using the hydrothermal carbonization process. Additionally, a thorough comprehension of the kinetics of combustion, gasification, and pyrolysis is crucial for the design of industrial processes, feasibility assessments, and scale-up.

{"title":"Thermal decomposition kinetics of dairy manure hydrochars","authors":"Kalidas Mainali , Majher I. Sarker , Charles A. Mullen , Brajendra K. Sharma , Madhav P. Yadav , Helen Ngo , Manuel Garcia-Perez","doi":"10.1016/j.joei.2025.102088","DOIUrl":"10.1016/j.joei.2025.102088","url":null,"abstract":"<div><div>Hydrothermal processes, as well as hydrothermal carbonization (HTC), have emerged as a promising technology for the conversion of high-moisture feedstocks. A total of six hydrochars were generated from dairy manure via H3PO4-catalyzed HTC at varying reaction temperatures and residence times. The heating value of hydrochars produced using HTC (25.64 MJ/kg) has improved significantly from raw dairy manure (17.16 MJ/kg). The kinetic parameters for the thermal decomposition of the manure and its hydrochars were estimated using the Friedman mathematical model. In a comparison of three reaction atmospheres (CO<sub>2</sub>, N<sub>2</sub>, and air), it was observed that lower activation energies were required in air environments for all specified hydrochars relative to the raw manure. Furthermore, Py-GC-MS studies revealed that light-oxygenated compounds were produced at 500 °C from the hydrochars upon flash pyrolysis. The acid treatment under autogenous pressure, significantly improved manure hydrochars physiochemical properties. The comprehensive theoretical and practical guidelines presented in this study for acid-promoted manure hydrochars indicate that dairy manure can be converted into a substitute energy source using the hydrothermal carbonization process. Additionally, a thorough comprehension of the kinetics of combustion, gasification, and pyrolysis is crucial for the design of industrial processes, feasibility assessments, and scale-up.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"120 ","pages":"Article 102088"},"PeriodicalIF":5.6,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insight into pyrolysis behavior of waste printed circuit boards using in-situ Py-TOF-MS combined with Py-GC/MS: Primary volatiles evolution and catalytic effect of coated copper

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-04 DOI: 10.1016/j.joei.2025.102080

Yunfei Wu , Bo Wang

The real-time detection of primary volatiles is essential for properly understanding the pyrolysis behaviors of waste printed circuit boards (WPCBs) and the catalytic effect of coated copper. In this study, in-situ pyrolysis time-of-flight mass spectrometry was used in conjunction with pyrolysis-gas chromatography/mass spectrometry to detect primary volatiles and identify the main compositions of pyrolysis oil. The results revealed that the presence of Cu has an obvious inhibitory effect on WPCBs pyrolysis, resulting in a decrease in formed phenolic and etheric compounds such as phenol (11.75 % in Cu-coated WPCBs vs 17.02 % in non-Cu WPCBs), p-isopropenylphenol (4.25 % vs 6.56 %) in the initial pyrolysis stage. Nevertheless, Cu can trigger the C-Br bond to fracture in brominated epoxy resin, and subsequently released •Br radicals are captured by active Cu to form coordination compound Cu…Br, thereby lowering the production of bromides such as CH₃Br (reduced by 0.44 %), 2-bromo-p-cymene (reduced by 0.84 %), and 2,6-dibromo-phenol (reduced by 0.49 %). As temperature increases, Cu promotes the degradation of WPCBs residues, especially the curing agent in it, and the released free radicals subsequently react to form macromolecular compounds like 1,1'-[1,2-ethanediylbis(oxy)] bis-benzene and 1-amino-8-naphthol-3,6-disulfonic acid. Additionally, debromination occurred at high temperatures as a result of the Cu-induced Ulmann cross-coupling reaction. The obtained results can provide the theoretical foundation for sustainable WPCBs conversion and debromination.

{"title":"Insight into pyrolysis behavior of waste printed circuit boards using in-situ Py-TOF-MS combined with Py-GC/MS: Primary volatiles evolution and catalytic effect of coated copper","authors":"Yunfei Wu , Bo Wang","doi":"10.1016/j.joei.2025.102080","DOIUrl":"10.1016/j.joei.2025.102080","url":null,"abstract":"<div><div>The real-time detection of primary volatiles is essential for properly understanding the pyrolysis behaviors of waste printed circuit boards (WPCBs) and the catalytic effect of coated copper. In this study, in-situ pyrolysis time-of-flight mass spectrometry was used in conjunction with pyrolysis-gas chromatography/mass spectrometry to detect primary volatiles and identify the main compositions of pyrolysis oil. The results revealed that the presence of Cu has an obvious inhibitory effect on WPCBs pyrolysis, resulting in a decrease in formed phenolic and etheric compounds such as phenol (11.75 % in Cu-coated WPCBs vs 17.02 % in non-Cu WPCBs), p-isopropenylphenol (4.25 % vs 6.56 %) in the initial pyrolysis stage. Nevertheless, Cu can trigger the C-Br bond to fracture in brominated epoxy resin, and subsequently released •Br radicals are captured by active Cu to form coordination compound Cu…Br, thereby lowering the production of bromides such as CH<sub>3</sub>Br (reduced by 0.44 %), 2-bromo-p-cymene (reduced by 0.84 %), and 2,6-dibromo-phenol (reduced by 0.49 %). As temperature increases, Cu promotes the degradation of WPCBs residues, especially the curing agent in it, and the released free radicals subsequently react to form macromolecular compounds like 1,1'-[1,2-ethanediylbis(oxy)] bis-benzene and 1-amino-8-naphthol-3,6-disulfonic acid. Additionally, debromination occurred at high temperatures as a result of the Cu-induced Ulmann cross-coupling reaction. The obtained results can provide the theoretical foundation for sustainable WPCBs conversion and debromination.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"120 ","pages":"Article 102080"},"PeriodicalIF":5.6,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Rapid and accurate prediction of molecular dynamics simulations using physics-informed LSTM networks in engine emission analysis: A case study of C3H6/NH3 pyrolysis for PAH formation

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-03 DOI: 10.1016/j.joei.2025.102090

Yuchao Yan , Tianfang Xie , Jinlong Liu

Molecular dynamics (MD) simulations are essential tools for analyzing internal combustion engine emissions, particularly in the study of polycyclic aromatic hydrocarbon (PAH) and soot formation; however, these simulations are computationally intensive, requiring significant resources and time. Long Short-Term Memory (LSTM) networks offer an efficient alternative for modeling time-dependent, strongly coupled, and high-dimensional chemical processes, enabling faster predictions without sacrificing accuracy. This study explores the feasibility of using LSTM networks to predict MD simulation results in the context of engine emissions, an area where the application of time-series deep learning models remains limited, by simulating PAH formation through the pyrolysis of C₃H₆ and NH₃ blends, a process characteristic of the localized oxygen-deficient environments in compression ignition engines. The results show that the LSTM model, trained on data from multiple C₃H₆/NH₃ blends, can predict species count variations for unseen blends, demonstrating strong potential for reducing computational costs. To improve model reliability and ensure adherence to conservation laws, physical constraints are incorporated into the loss function during training. Comparison of LSTM and physics-informed LSTM (PI-LSTM) performance reveals that integrating carbon balance constraints, a critical factor in internal combustion engine research, limits fluctuations in total carbon count, addressing the limitations of purely data-driven models. While such an innovative approach introduces a trade-off between prediction accuracy for individual species and physical consistency, it enhances the model overall reliability. Overall, this study demonstrates the potential of combining machine learning, particularly PI-LSTM, with MD simulations to reduce computational costs and maintain predictive accuracy in internal combustion engine emission research, offering the engine research community a powerful and transferable tool for tackling complex combustion challenges.

{"title":"Rapid and accurate prediction of molecular dynamics simulations using physics-informed LSTM networks in engine emission analysis: A case study of C3H6/NH3 pyrolysis for PAH formation","authors":"Yuchao Yan , Tianfang Xie , Jinlong Liu","doi":"10.1016/j.joei.2025.102090","DOIUrl":"10.1016/j.joei.2025.102090","url":null,"abstract":"<div><div>Molecular dynamics (MD) simulations are essential tools for analyzing internal combustion engine emissions, particularly in the study of polycyclic aromatic hydrocarbon (PAH) and soot formation; however, these simulations are computationally intensive, requiring significant resources and time. Long Short-Term Memory (LSTM) networks offer an efficient alternative for modeling time-dependent, strongly coupled, and high-dimensional chemical processes, enabling faster predictions without sacrificing accuracy. This study explores the feasibility of using LSTM networks to predict MD simulation results in the context of engine emissions, an area where the application of time-series deep learning models remains limited, by simulating PAH formation through the pyrolysis of C<sub>3</sub>H<sub>6</sub> and NH<sub>3</sub> blends, a process characteristic of the localized oxygen-deficient environments in compression ignition engines. The results show that the LSTM model, trained on data from multiple C<sub>3</sub>H<sub>6</sub>/NH<sub>3</sub> blends, can predict species count variations for unseen blends, demonstrating strong potential for reducing computational costs. To improve model reliability and ensure adherence to conservation laws, physical constraints are incorporated into the loss function during training. Comparison of LSTM and physics-informed LSTM (PI-LSTM) performance reveals that integrating carbon balance constraints, a critical factor in internal combustion engine research, limits fluctuations in total carbon count, addressing the limitations of purely data-driven models. While such an innovative approach introduces a trade-off between prediction accuracy for individual species and physical consistency, it enhances the model overall reliability. Overall, this study demonstrates the potential of combining machine learning, particularly PI-LSTM, with MD simulations to reduce computational costs and maintain predictive accuracy in internal combustion engine emission research, offering the engine research community a powerful and transferable tool for tackling complex combustion challenges.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"120 ","pages":"Article 102090"},"PeriodicalIF":5.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of nano-particle emissions from gasoline direct injection engines utilizing non-thermal plasma and nickel foam technologies

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-02 DOI: 10.1016/j.joei.2025.102081

Pichitpon Neamyou , Sak Sittichompoo , Boonlue Sawatmongkhon , Nathinee Theinnoi , Kampanart Theinnoi

The present investigation aims to assess the efficacy of the integration of Non-Thermal Plasma (NTP) technology with porous substrates, particularly nickel foam, for the mitigation of particulate matter (PM) emissions originating from Gasoline Direct Injection (GDI) engines. GDI engines, while offering enhanced fuel efficiency, are associated with higher concentrations of ultrafine PM, which pose significant environmental and health risks. Nickel foam, selected for its high surface area, thermal stability, and catalytic properties, is utilized to enhance PM filtration. Experimental results demonstrate that the integration of NTP technology with nickel foam significantly reduces both the number and mass of particles emitted by GDI engines. Specifically, PM removal efficiencies of up to 83 % were achieved at higher voltages (10 kV). However, energy consumption was found to increase substantially with voltage, emphasizing the need to optimize the balance between energy input and PM reduction. The study further reveals that increasing the thickness of the nickel foam from 0 to 6 mm enhances PM capture, but also increases the specific energy density required for PM reduction. The results showed that at lower voltages (2–4 kV), the combination of NTP and nickel foam was particularly effective, achieving significant PM reduction with lower energy consumption.

{"title":"Analysis of nano-particle emissions from gasoline direct injection engines utilizing non-thermal plasma and nickel foam technologies","authors":"Pichitpon Neamyou , Sak Sittichompoo , Boonlue Sawatmongkhon , Nathinee Theinnoi , Kampanart Theinnoi","doi":"10.1016/j.joei.2025.102081","DOIUrl":"10.1016/j.joei.2025.102081","url":null,"abstract":"<div><div>The present investigation aims to assess the efficacy of the integration of Non-Thermal Plasma (NTP) technology with porous substrates, particularly nickel foam, for the mitigation of particulate matter (PM) emissions originating from Gasoline Direct Injection (GDI) engines. GDI engines, while offering enhanced fuel efficiency, are associated with higher concentrations of ultrafine PM, which pose significant environmental and health risks. Nickel foam, selected for its high surface area, thermal stability, and catalytic properties, is utilized to enhance PM filtration. Experimental results demonstrate that the integration of NTP technology with nickel foam significantly reduces both the number and mass of particles emitted by GDI engines. Specifically, PM removal efficiencies of up to 83 % were achieved at higher voltages (10 kV). However, energy consumption was found to increase substantially with voltage, emphasizing the need to optimize the balance between energy input and PM reduction. The study further reveals that increasing the thickness of the nickel foam from 0 to 6 mm enhances PM capture, but also increases the specific energy density required for PM reduction. The results showed that at lower voltages (2–4 kV), the combination of NTP and nickel foam was particularly effective, achieving significant PM reduction with lower energy consumption.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"120 ","pages":"Article 102081"},"PeriodicalIF":5.6,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Overview for methanol and formaldehyde unregulated emissions of methanol fueled engines 甲醇燃料发动机的甲醇和甲醛未受管制排放概况

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-01 DOI: 10.1016/j.joei.2025.102089

Hong Wei , Ziye Zhang , Xinru Zhang , Fengjuan Dong , Wangfang Yuan , Hao Chen

Methanol can be classified into green methanol, biomass methanol, and fossil fuel derived methanol based on the abundant feedstocks, and it has been widely applied on road and marine transport vehicles. However, the utilization of methanol is favorable for reducing carbon monoxide (CO), hydrocarbon (HC), and particulate matter (PM) engine emissions, its unregulated emissions increase compared to traditional gasoline or diesel engines. The unregulated emissions include formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, methanol, acetone, ethanol and etc., among which the unburned methanol and formaldehyde are predominant. The unburned methanol is mainly generated by the crevice and quenching effects, and formaldehyde by the incomplete oxidation of methanol in the exhaust system. Factors including exhaust gas recirculation (EGR), engine load and speed, intake and exhaust temperature, methanol substitution rate (MSR), and injection strategy affect the unburned methanol and formaldehyde emissions to a certain extent. Liquid chromatography (LC) and gas chromatography (GC) measure unburned methanol and formaldehyde emissions more accurately than Fourier transform infrared (FTIR), but FTIR can detect data on unburned methanol and formaldehyde emissions in real time under variable operating conditions or online for multiple emissions simultaneously. After-treatment devices such as diesel oxidation catalyst (DOC), particle oxidation catalyst (POC), or three-way catalyst (TWC) can reduce unburned methanol or formaldehyde emissions. The combination of DOC and POC is superior to a single DOC to remove the unburned methanol and formaldehyde emissions. The review provides a systemic analysis on the generation, hazard, measurement, and disposal of methanol and formaldehyde and promotes the clean application of methanol fuel.

根据原料的丰富程度，甲醇可分为绿色甲醇、生物质甲醇和化石燃料衍生甲醇。然而，甲醇的使用有利于减少发动机的一氧化碳（CO）、碳氢化合物（HC）和颗粒物（PM）排放，但与传统的汽油或柴油发动机相比，甲醇的非规范排放会增加。未受管制的排放物包括甲醛、乙醛、丙醛、正丁醛、甲醇、丙酮、乙醇等，其中以未燃烧的甲醇和甲醛为主。未燃甲醇主要是由缝隙和淬火效应产生的，甲醛则是由甲醇在排气系统中不完全氧化产生的。废气再循环（EGR）、发动机负荷和转速、进气和排气温度、甲醇替代率（MSR）和喷射策略等因素都会在一定程度上影响未燃甲醇和甲醛的排放。液相色谱法（LC）和气相色谱法（GC）比傅立叶变换红外光谱法（FTIR）能更准确地测量未燃甲醇和甲醛的排放，但傅立叶变换红外光谱法能在不同的运行条件下实时检测未燃甲醇和甲醛的排放数据，或同时在线检测多种排放物。柴油氧化催化剂 (DOC)、颗粒氧化催化剂 (POC) 或三元催化剂 (TWC) 等后处理装置可以减少未燃烧甲醇或甲醛的排放。DOC 和 POC 的组合在去除未燃烧甲醇和甲醛排放方面优于单一 DOC。该综述对甲醇和甲醛的产生、危害、测量和处置进行了系统分析，促进了甲醇燃料的清洁应用。

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引用次数: 0

Deactivation effect of different Pb salts over Fe/Zr-W catalyst for selective catalytic reduction of NO with NH3

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-01 DOI: 10.1016/j.joei.2025.102087

Liang Wang , Shan Ren , Xiaodi Li , Chi He , Chunli Zheng , Xinzhe Li , Shouning Chai , Chunbao Charles Xu

Deactivation on NH₃-SCR catalyst surface by heavy metal species continues to hinder it long-term usage lifetime in flue gas treatment. A deeper insight into the poisoning effect of different Pb species on catalysts is crucial for designing denitrification catalysts with anti-Pb property. Herein, the obtained Fe/Zr-W catalyst was modified through multiple Pb salts (Pb(NO₃)₂, PbCl₂, and PbSO₄) to assess the different impact caused by various Pb species. The results showed that different Pb species led to varying levels of catalyst deactivation. Pb(NO₃)₂ and PbCl₂ caused different degrees of deactivation in the Fe/Zr-W catalyst, associated with the decrease in redox cycling capacity, acidic sites, and surface adsorption oxygen. However, PbSO₄ inversely enhanced the acidic site density of catalyst, which favored NH₃ adsorption but significantly decreased the conversion selectivity in catalytic process. Possible deactivation pathway differentiation among Pb salts over Fe/Zr-W catalyst was established. This work revealed insights into the different poisoning pathway of various Pb salts, contributing to the development of denitration catalysts with enhanced Pb tolerance.

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引用次数: 0

Evaluating raw bio-oil from wood chip pyrolysis as a diesel substitute: Combustion and emissions performance

IF 5.6 2区工程技术 Q2 ENERGY & FUELS

Journal of The Energy Institute

Pub Date : 2025-04-01 DOI: 10.1016/j.joei.2025.102078

Yue Yu , Deqing Mei , Zhixiang Yan , Cheng Wang , Pei Feng , Ning Wei

Pyrolysis Biomass oil (Bio-oil) has disadvantages such as high water content, high corrosion, and high viscosity, so it is necessary to improve the quality of bio-pyrolysis oil. Via catalytic esterification combined with alkylation, pyrolysis bio-oil was upgraded. Bio-oil blends were prepared by mixing 5 %, 10 %, and 15 % volume of the upgraded bio-oil with diesel, respectively, and their combustion and emission performances were assessed in a practical diesel engine. The results showed that after the refining process from crude bio-oil to refined bio-oil, the acids mass fraction decreased from 12.0 % to 1.8 % and the esters mass fraction increased from 0.5 % to 9.6 %, the aldehydes and ketones mass fraction decreased from 22.3 % to 4.4 %, and the ethers mass fraction increased from 0.7 % to 37.8 %. At the same load, increasing the ratio of the upgraded fuel led to a gradual deterioration in the equivalent specific fuel consumption as well as the brake thermal efficiency. In addition, the ignition timing was advanced, and the ignition delay was shortened. The heat release rate and cylinder pressure peak in the initial combustion stage decreased, in turn, while the heat release rate and cylinder pressure peak in the main combustion stage increased. At BMEP = 0.23 MPa of 1800 rpm, the brake thermal efficiency was reduced by 2.1 %, 4.2 %, and 7.0 %, respectively, while at high load conditions, the reduction in brake thermal efficiency of mixed fuel tended to level off. At low loads, due to the small fuel amount injected per cycle, the low temperature in the cylinder inhibited the further oxidation of hydrocarbon (HC) and carbon monoxide (CO), and fewer nitrogen oxides (NO_x) and soot were generated as well. Therefore, compared with that at high loads, there was no significant difference in NO_x and particulate matter (PM) emissions between various fuels, while an obvious difference in HC and CO emissions was found.

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引用次数: 0