Fuel最新文献_第8页

A review of gas hydrate formation characteristics at interfaces

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134863

Shihang Rao , Zhenchao Li , Hailong Lu , Yajun Deng

Gas hydrates are crystalline solids, where gas molecules are trapped in cavities constructed by hydrogen-bonded water molecules under relatively high-pressure and low-temperature conditions. Hydrates play a crucial role in the global energy system, serving as possible blockages in traditional oil and gas transportation, ideal clean energy sources formed naturally, and a potential long-term carbon sequestration media. Besides, it is with great potential to apply hydrate-based technology in environmental fields, such as gas separation and purification, seawater desalination, wastewater purification, etc. Whether in natural or industrial systems, hydrates share interfaces with a variety of substances, including gases, different liquids (such as oil, aqueous solutions), and different solids (such as sediments, pipe walls), among others. For the enhanced progress of hydrate-based technology, it is of great significance to conduct an in-depth study into the unique features of hydrate formation at interfaces and the corresponding factors. On the basis, this paper reviews the significant insights generated by recent researches in understanding of hydrate nucleation and growth mechanisms at interfaces. Special focus is laid on the interactions among gas, liquid and solid, as well as the impacts of other prominent factors (driving force, additives, gas composition etc.) on hydrate formation. The essential physical and chemical insights presented in this review may be of worth in better design of the research methods and industrial applications.

{"title":"A review of gas hydrate formation characteristics at interfaces","authors":"Shihang Rao , Zhenchao Li , Hailong Lu , Yajun Deng","doi":"10.1016/j.fuel.2025.134863","DOIUrl":"10.1016/j.fuel.2025.134863","url":null,"abstract":"<div><div>Gas hydrates are crystalline solids, where gas molecules are trapped in cavities constructed by hydrogen-bonded water molecules under relatively high-pressure and low-temperature conditions. Hydrates play a crucial role in the global energy system, serving as possible blockages in traditional oil and gas transportation, ideal clean energy sources formed naturally, and a potential long-term carbon sequestration media. Besides, it is with great potential to apply hydrate-based technology in environmental fields, such as gas separation and purification, seawater desalination, wastewater purification, etc. Whether in natural or industrial systems, hydrates share interfaces with a variety of substances, including gases, different liquids (such as oil, aqueous solutions), and different solids (such as sediments, pipe walls), among others. For the enhanced progress of hydrate-based technology, it is of great significance to conduct an in-depth study into the unique features of hydrate formation at interfaces and the corresponding factors. On the basis, this paper reviews the significant insights generated by recent researches in understanding of hydrate nucleation and growth mechanisms at interfaces. Special focus is laid on the interactions among gas, liquid and solid, as well as the impacts of other prominent factors (driving force, additives, gas composition etc.) on hydrate formation. The essential physical and chemical insights presented in this review may be of worth in better design of the research methods and industrial applications.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134863"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Efficient and durable system design for ammonia-fueled solid oxide fuel cells using multiscale multiphysics modeling approach

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134837

Arash Nemati , Hossein Nami , Javid Beyrami , Rafael Nogueira Nakashima , Henrik Lund Frandsen

It is crucial to consider all of the scales and underlying physics to design a durable and efficient ammonia-fueled SOFC system. Therefore, a novel multiscale multiphysics modeling approach is used in this study as a design tool to investigate various features of ammonia-fueled SOFC systems, stacks, and cells including performance and nitriding degradation. Different system configurations are designed and influence of anode off-gas recirculation (AOR) and ammonia pre-cracking is investigated. Results indicate the impact of the design changes on efficiency and nitriding degradation. Air flow rate and inlet temperature should be controlled for different configurations to keep the temperature of cells in the stacks inside a desired range. Implementing the AOR showed a considerable improvement in efficiency as for 0 %, 50 %, 70 %, and 90 % AOR rates, system efficiencies are around 53 %, 63 %, 70 %, and 75 %, respectively. To avoid nitriding at the given operating conditions, around 90 % external pre-cracking is required. A system with 90 % of pre-cracking and 90 % AOR is selected as the most efficient and durable system configuration, for the technology at hand. Pressure drops in the system components, particularly on the air side, should be minimized to achieve high efficiency in cases with high ammonia pre-cracking ratios.

{"title":"Efficient and durable system design for ammonia-fueled solid oxide fuel cells using multiscale multiphysics modeling approach","authors":"Arash Nemati , Hossein Nami , Javid Beyrami , Rafael Nogueira Nakashima , Henrik Lund Frandsen","doi":"10.1016/j.fuel.2025.134837","DOIUrl":"10.1016/j.fuel.2025.134837","url":null,"abstract":"<div><div>It is crucial to consider all of the scales and underlying physics to design a durable and efficient ammonia-fueled SOFC system. Therefore, a novel multiscale multiphysics modeling approach is used in this study as a design tool to investigate various features of ammonia-fueled SOFC systems, stacks, and cells including performance and nitriding degradation. Different system configurations are designed and influence of anode off-gas recirculation (AOR) and ammonia pre-cracking is investigated. Results indicate the impact of the design changes on efficiency and nitriding degradation. Air flow rate and inlet temperature should be controlled for different configurations to keep the temperature of cells in the stacks inside a desired range. Implementing the AOR showed a considerable improvement in efficiency as for 0 %, 50 %, 70 %, and 90 % AOR rates, system efficiencies are around 53 %, 63 %, 70 %, and 75 %, respectively. To avoid nitriding at the given operating conditions, around 90 % external pre-cracking is required. A system with 90 % of pre-cracking and 90 % AOR is selected as the most efficient and durable system configuration, for the technology at hand. Pressure drops in the system components, particularly on the air side, should be minimized to achieve high efficiency in cases with high ammonia pre-cracking ratios.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134837"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Computationally inexpensive CFD modeling of sewage sludge and waste additive combustion experiments in an entrained flow reactor

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134797

Benjamin Ortner , Christian Schmidberger , René Prieler , Christoph Hochenauer

A computationally inexpensive, mixture-fraction-based CFD model was applied to investigate the combustion characteristics of two types of sewage sludge powder. These were mixed with meat and bone meal (MBM) and cement bypass dust (BPD) as additives. Experiments on a semi-industrial furnace were performed to obtain validation data. A wide range of operating conditions across eight different scenarios, varying by sludge type, additive combinations, and combustion settings, including over- and substoichiometric conditions as well as slight oxygen-enhancement were tested. All fuel-additive mixtures were adjusted to a basicity (

B 1 = C a O / S i O_{2}

) of one. Numerical simulations of entrained flow combustion were performed, and the CFD model’s predictions were validated against the experimental measurements and observations. Results showed that MBM had a significant impact on combustion behavior. When MBM was used to adjust the basicity, it increased the heat release in the furnace by up to 57% for sewage sludge with a lower initial basicity. This effect was attributed to the higher heating value of MBM. However, the MBM also displayed a slower burnout rate compared to sewage sludge powder with BPD, indicated by spatial trends in the gas phase measurements. This was likely due to the larger particle size of the MBM. In contrast, BPD had a negligible impact on combustion behavior. Overall, the CFD model demonstrated very good agreement with the experimental data, confirming its effectiveness as a tool for research, development, and process up-scaling.

{"title":"Computationally inexpensive CFD modeling of sewage sludge and waste additive combustion experiments in an entrained flow reactor","authors":"Benjamin Ortner , Christian Schmidberger , René Prieler , Christoph Hochenauer","doi":"10.1016/j.fuel.2025.134797","DOIUrl":"10.1016/j.fuel.2025.134797","url":null,"abstract":"<div><div>A computationally inexpensive, mixture-fraction-based CFD model was applied to investigate the combustion characteristics of two types of sewage sludge powder. These were mixed with meat and bone meal (MBM) and cement bypass dust (BPD) as additives. Experiments on a semi-industrial furnace were performed to obtain validation data. A wide range of operating conditions across eight different scenarios, varying by sludge type, additive combinations, and combustion settings, including over- and substoichiometric conditions as well as slight oxygen-enhancement were tested. All fuel-additive mixtures were adjusted to a basicity (<span><math><mrow><mi>B</mi><mn>1</mn><mo>=</mo><mi>C</mi><mi>a</mi><mi>O</mi><mo>/</mo><mi>S</mi><mi>i</mi><msub><mrow><mi>O</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>) of one. Numerical simulations of entrained flow combustion were performed, and the CFD model’s predictions were validated against the experimental measurements and observations. Results showed that MBM had a significant impact on combustion behavior. When MBM was used to adjust the basicity, it increased the heat release in the furnace by up to 57% for sewage sludge with a lower initial basicity. This effect was attributed to the higher heating value of MBM. However, the MBM also displayed a slower burnout rate compared to sewage sludge powder with BPD, indicated by spatial trends in the gas phase measurements. This was likely due to the larger particle size of the MBM. In contrast, BPD had a negligible impact on combustion behavior. Overall, the CFD model demonstrated very good agreement with the experimental data, confirming its effectiveness as a tool for research, development, and process up-scaling.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"389 ","pages":"Article 134797"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improvement of low-temperature NOx reduction performance of NH3-SCR with O3 injection under diesel engine transient conditions

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134817

Yanghwa Kim , Ocktaeck Lim , Hongsuk Kim

NH₃-based selective catalytic reduction (SCR) is an effective technology for reducing NO_x emissions, a major contributor to air pollution, but its efficiency significantly decreases at temperatures below 200°C. To enhance low-temperature NO_x reduction, O₃ was injected into the exhaust gas during the initial 600 s of the World Harmonized Transient Cycle (WHTC) cold phase in a diesel engine using a Cu/SSZ-13 catalyst. O₃ promotes the oxidation of NO to NO₂, which reacts with NH₃ below 150°C to form NH₄NO₃, thereby improving NO_x reduction efficiency. While NH₄NO₃ accumulates on the catalyst at low temperatures without participating in the SCR reaction, it acts as an intermediate for fast SCR as the temperature rises, further enhancing NO_x reduction. Furthermore, machine learning was applied to predict optimal NO_x reduction rates based on the O₃/NO molar ratio, revealing that the highest efficiency at catalyst inlet temperatures below 150°C is achieved when the O₃/NO ratio is set to 1. This approach demonstrates the potential of O₃ injection combined with data-driven optimization to improve SCR performance under cold-start conditions.

{"title":"Improvement of low-temperature NOx reduction performance of NH3-SCR with O3 injection under diesel engine transient conditions","authors":"Yanghwa Kim , Ocktaeck Lim , Hongsuk Kim","doi":"10.1016/j.fuel.2025.134817","DOIUrl":"10.1016/j.fuel.2025.134817","url":null,"abstract":"<div><div>NH<sub>3</sub>-based selective catalytic reduction (SCR) is an effective technology for reducing NO<sub>x</sub> emissions, a major contributor to air pollution, but its efficiency significantly decreases at temperatures below 200°C. To enhance low-temperature NO<sub>x</sub> reduction, O<sub>3</sub> was injected into the exhaust gas during the initial 600 s of the World Harmonized Transient Cycle (WHTC) cold phase in a diesel engine using a Cu/SSZ-13 catalyst. O<sub>3</sub> promotes the oxidation of NO to NO<sub>2</sub>, which reacts with NH<sub>3</sub> below 150°C to form NH<sub>4</sub>NO<sub>3</sub>, thereby improving NO<sub>x</sub> reduction efficiency. While NH<sub>4</sub>NO<sub>3</sub> accumulates on the catalyst at low temperatures without participating in the SCR reaction, it acts as an intermediate for fast SCR as the temperature rises, further enhancing NO<sub>x</sub> reduction. Furthermore, machine learning was applied to predict optimal NO<sub>x</sub> reduction rates based on the O<sub>3</sub>/NO molar ratio, revealing that the highest efficiency at catalyst inlet temperatures below 150°C is achieved when the O<sub>3</sub>/NO ratio is set to 1. This approach demonstrates the potential of O<sub>3</sub> injection combined with data-driven optimization to improve SCR performance under cold-start conditions.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134817"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Enhanced NH3-SCR performance of high-silica MER zeolite via template synthesis

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134818

Yanhua Wang , Xiaoning Ren , Kaixiang Li , Yuankai Shao , Yang Zhou , Minru Zhao , Caixia Liu , Yatao Liu , Xi Liu , Anqi Dong , Hanming Wu , Maoxuan Wang , Lingwei Meng , Wang Zhang , Zhenguo Li , Qingling Liu

Amid increasingly stringent regulations on NOx emissions from diesel vehicles, Cu-based zeolite catalysts for ammonia selective catalytic reduction (NH₃-SCR) are considered among the most effective solutions. MER zeolite, featuring a three-dimensional (3D) topology with 8-membered ring (8 MR) micropores, is typically Al-rich (Si/Al < 3) in conventional template-free synthesis. In this study, hierarchical O-MER zeolite with a higher Si/Al ratio (6.01) was efficiently synthesized using N, N-1, 1, 2, 6-tetramethylpiperidine as an organic template via inter-zeolite conversion over a crystallization period of 7–72 h. Compared to C-MER zeolite synthesized template-free, the Cu-based MER zeolite exhibited significantly enhanced NH₃-SCR catalytic performance, achieving over 90 % NOx conversion within the 220–550 °C range for the fresh sample. Even after hydrothermal aging at 750 °C for 16 h, the sample maintained over 80 % NOx conversion between 250 and 550 °C. Comprehensive characterization revealed that hydrothermal aging partially degraded the crystalline structure of O-MER zeolite, notably reducing the number of acid sites, particularly Z-[Cu²⁺(OH)⁻]⁺, which decreased NO activation and storage, thereby impacting low-temperature activity. The sustainable synthesis of MER zeolite and its robust catalytic performance present promising candidates for the future development of efficient and cost-effective SCR catalysts.

{"title":"Enhanced NH3-SCR performance of high-silica MER zeolite via template synthesis","authors":"Yanhua Wang , Xiaoning Ren , Kaixiang Li , Yuankai Shao , Yang Zhou , Minru Zhao , Caixia Liu , Yatao Liu , Xi Liu , Anqi Dong , Hanming Wu , Maoxuan Wang , Lingwei Meng , Wang Zhang , Zhenguo Li , Qingling Liu","doi":"10.1016/j.fuel.2025.134818","DOIUrl":"10.1016/j.fuel.2025.134818","url":null,"abstract":"<div><div>Amid increasingly stringent regulations on NOx emissions from diesel vehicles, Cu-based zeolite catalysts for ammonia selective catalytic reduction (NH<sub>3</sub>-SCR) are considered among the most effective solutions. MER zeolite, featuring a three-dimensional (3D) topology with 8-membered ring (8 MR) micropores, is typically Al-rich (Si/Al < 3) in conventional template-free synthesis. In this study, hierarchical O-MER zeolite with a higher Si/Al ratio (6.01) was efficiently synthesized using N, N-1, 1, 2, 6-tetramethylpiperidine as an organic template via inter-zeolite conversion over a crystallization period of 7–72 h. Compared to C-MER zeolite synthesized template-free, the Cu-based MER zeolite exhibited significantly enhanced NH<sub>3</sub>-SCR catalytic performance, achieving over 90 % NOx conversion within the 220–550 °C range for the fresh sample. Even after hydrothermal aging at 750 °C for 16 h, the sample maintained over 80 % NOx conversion between 250 and 550 °C. Comprehensive characterization revealed that hydrothermal aging partially degraded the crystalline structure of O-MER zeolite, notably reducing the number of acid sites, particularly Z-[Cu<sup>2+</sup>(OH)<sup>−</sup>]<sup>+</sup>, which decreased NO activation and storage, thereby impacting low-temperature activity. The sustainable synthesis of MER zeolite and its robust catalytic performance present promising candidates for the future development of efficient and cost-effective SCR catalysts.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134818"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Synthesis of high yield mesoporous silica for efficient CO2 adsorption using coal gasification fine slag

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134840

Zekai Miao , Hao Ge , Xinran Han , Rui Wu , Hai Zhu , Congchao Zhang , Shengping Wang

The coal gasification fine slag (FS) is a solid waste rich in Si components. The preparation of high-performance mesoporous silica for CO₂ capture using FS as raw materials will alleviate environmental pollution. The alkali-fusion method was used to obtain the high activated Si-containing precursor which could be completely dissolved in NaOH solution with low alkalinity concentration (3 %). The mesoporous silica with highly ordered hexagonal phase was prepared which had high surface area of 1629 m²/g and pore volume of 0.8 cm³/g. The Si concentration had the great effect on the yield of mesoporous silica and the mechanism for the formation and growth of mesoporous silica between high and low Si-precursor concentration was different. In the preparation process for high yield of mesoporous silica, the silicate ions primarily tended to adsorb around the cetyltrimethylammonium bromide micelles to form nuclei and then the silicate reacted preferentially with the surface silanol groups on the existing particles rather than generating new nuclei. The condensation of the silicate at the external surface of the surfactant micelles occurred to grow into large particles. However, the mesoporous silica particles formation in the lower concentration of silicate species in the alkali solutions was mainly contributed to the interactions between silicate species and CTAB rather than the deposition of silica species. The mesoporous silica showed high CO₂ adsorption performance. The breakthrough time of MS-8 occurred at 22 min and CO₂ adsorption capacity was 2.3 mmol/g at 25 °C. All these results suggest that the silica in fine slag could be fully utilized to prepare mesoporous silica which had a great potential to be used for practical and industrial CO₂ adsorption applications.

{"title":"Synthesis of high yield mesoporous silica for efficient CO2 adsorption using coal gasification fine slag","authors":"Zekai Miao , Hao Ge , Xinran Han , Rui Wu , Hai Zhu , Congchao Zhang , Shengping Wang","doi":"10.1016/j.fuel.2025.134840","DOIUrl":"10.1016/j.fuel.2025.134840","url":null,"abstract":"<div><div>The coal gasification fine slag (FS) is a solid waste rich in Si components. The preparation of high-performance mesoporous silica for CO<sub>2</sub> capture using FS as raw materials will alleviate environmental pollution. The alkali-fusion method was used to obtain the high activated Si-containing precursor which could be completely dissolved in NaOH solution with low alkalinity concentration (3 %). The mesoporous silica with highly ordered hexagonal phase was prepared which had high surface area of 1629 m<sup>2</sup>/g and pore volume of 0.8 cm<sup>3</sup>/g. The Si concentration had the great effect on the yield of mesoporous silica and the mechanism for the formation and growth of mesoporous silica between high and low Si-precursor concentration was different. In the preparation process for high yield of mesoporous silica, the silicate ions primarily tended to adsorb around the cetyltrimethylammonium bromide micelles to form nuclei and then the silicate reacted preferentially with the surface silanol groups on the existing particles rather than generating new nuclei. The condensation of the silicate at the external surface of the surfactant micelles occurred to grow into large particles. However, the mesoporous silica particles formation in the lower concentration of silicate species in the alkali solutions was mainly contributed to the interactions between silicate species and CTAB rather than the deposition of silica species. The mesoporous silica showed high CO<sub>2</sub> adsorption performance. The breakthrough time of MS-8 occurred at 22 min and CO<sub>2</sub> adsorption capacity was 2.3 mmol/g at 25 °C. All these results suggest that the silica in fine slag could be fully utilized to prepare mesoporous silica which had a great potential to be used for practical and industrial CO<sub>2</sub> adsorption applications.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134840"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Continuous conversion of tall oil over Ni-Cu/SAPO-11 to a sustainable aviation fuel blendstock with excellent seal swelling properties

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134695

Great C. Umenweke , Robert B. Pace , Mathis Metais , Olivier Heintz , Gilles Caboche , Eduardo Santillan-Jimenez

In this contribution, distilled tall oil (DTO) was upgraded to synthetic aromatic kerosene (SAK) – for use as Sustainable Aviation Fuel (SAF) blendstock – via decarboxylation/decarbonylation, a process that offers an attractive alternative to hydrodeoxygenation since it enables the use of lower amounts and pressures of hydrogen, feedstocks of low purity and cost, and simple supported metal catalysts. Quantitative conversion of DTO was obtained over Ni-Cu/SAPO-11 in a continuous fixed bed reactor for 144 h time-on-stream. Notably, reaction products included all types of hydrocarbons present in jet fuel, namely, n-alkanes, iso-alkanes, cycloalkanes, and aromatics, with high selectivity (>80 %) to aromatics within the jet fuel boiling point range. The volume swell percentage of a Buna-N O-ring immersed in the SAK mixture produced was measured and found to be comparable to approved SAF-containing blends. Catalyst characterization via several techniques – including N₂-physisorption, H₂-chemisorption, x-ray diffraction, x-ray photoelectron spectroscopy, microscopy, and temperature-programmed techniques – was performed to rationalize trends and elucidate structure–activity relationships.

{"title":"Continuous conversion of tall oil over Ni-Cu/SAPO-11 to a sustainable aviation fuel blendstock with excellent seal swelling properties","authors":"Great C. Umenweke , Robert B. Pace , Mathis Metais , Olivier Heintz , Gilles Caboche , Eduardo Santillan-Jimenez","doi":"10.1016/j.fuel.2025.134695","DOIUrl":"10.1016/j.fuel.2025.134695","url":null,"abstract":"<div><div>In this contribution, distilled tall oil (DTO) was upgraded to synthetic aromatic kerosene (SAK) – for use as Sustainable Aviation Fuel (SAF) blendstock – via decarboxylation/decarbonylation, a process that offers an attractive alternative to hydrodeoxygenation since it enables the use of lower amounts and pressures of hydrogen, feedstocks of low purity and cost, and simple supported metal catalysts. Quantitative conversion of DTO was obtained over Ni-Cu/SAPO-11 in a continuous fixed bed reactor for 144 h time-on-stream. Notably, reaction products included all types of hydrocarbons present in jet fuel, namely, n-alkanes, <em>iso</em>-alkanes, cycloalkanes, and aromatics, with high selectivity (>80 %) to aromatics within the jet fuel boiling point range. The volume swell percentage of a Buna-N O-ring immersed in the SAK mixture produced was measured and found to be comparable to approved SAF-containing blends. Catalyst characterization via several techniques – including N<sub>2</sub>-physisorption, H<sub>2</sub>-chemisorption, x-ray diffraction, x-ray photoelectron spectroscopy, microscopy, and temperature-programmed techniques – was performed to rationalize trends and elucidate structure–activity relationships.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134695"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Ni-modified 3D porous carbon materials for upgrading coal pyrolysis volatiles to improve tar quality and inhibit coke formation

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-28 DOI: 10.1016/j.fuel.2025.134775

Qian Wang , Ting Li , Qian Tian , Nichen Wang , Yanfeng Shen , Lunjing Yan , Meijun Wang , Liping Chang , Weiren Bao

Catalytic upgrading of pyrolysis volatiles allows for the clean and efficient conversion and utilization of low-rank coal. Serial Ni-modified 3D porous carbon materials with varying Ni content were developed for catalytic upgrading of volatiles using fat coal and biochar as carbon sources. Ni-doped carbon materials (M_XFC and M_XFAC) and Ni-loaded carbon materials (L_XFC and L_XFAC) were prepared using the mixing, loading, carbonization, and steam activating methods. Ni-doped carbon materials with high fractal dimensions were analyzed using Synchrotron Small-Angle X-ray scattering (SAXS). Compared to Ni-loaded carbon materials, Ni-doped materials were more effective in increasing light oil yield and decreasing coke yield while still maintaining tar yield. This was particularly prominent for M₅FC, as its hydrogenation and cracking performance can be effectively balanced for volatile reactions. Hydrogen-rich radicals and radical fragments from volatiles are beneficial to “spatiotemporal matching” under the synergistic effect of high fractal dimensions and well-dispersed Ni active sites within the carbon skeleton. Consequently, the yield of light oil could increase by 1.71 wt%, while the coke yield decreased by 0.32 wt% compared to inert quartz beads. Also, coke in tar (Coke-T) was rich in 3–5 cyclic aromatics structures with more carbon defects. Conversely, other Ni-modified carbon materials intensified the condensation reactions of volatiles due to the strong catalytic cracking performances of the surface-loaded Ni, oxygen-containing functional groups, and carbon structural defects. As a result, some volatiles were converted to gas and coke, and the resultant Coke-T contained more ordered carbon structures with poorer combustion reactivity.

{"title":"Ni-modified 3D porous carbon materials for upgrading coal pyrolysis volatiles to improve tar quality and inhibit coke formation","authors":"Qian Wang , Ting Li , Qian Tian , Nichen Wang , Yanfeng Shen , Lunjing Yan , Meijun Wang , Liping Chang , Weiren Bao","doi":"10.1016/j.fuel.2025.134775","DOIUrl":"10.1016/j.fuel.2025.134775","url":null,"abstract":"<div><div>Catalytic upgrading of pyrolysis volatiles allows for the clean and efficient conversion and utilization of low-rank coal. Serial Ni-modified 3D porous carbon materials with varying Ni content were developed for catalytic upgrading of volatiles using fat coal and biochar as carbon sources. Ni-doped carbon materials (M<sub>X</sub>FC and M<sub>X</sub>FAC) and Ni-loaded carbon materials (L<sub>X</sub>FC and L<sub>X</sub>FAC) were prepared using the mixing, loading, carbonization, and steam activating methods. Ni-doped carbon materials with high fractal dimensions were analyzed using Synchrotron Small-Angle X-ray scattering (SAXS). Compared to Ni-loaded carbon materials, Ni-doped materials were more effective in increasing light oil yield and decreasing coke yield while still maintaining tar yield. This was particularly prominent for M<sub>5</sub>FC, as its hydrogenation and cracking performance can be effectively balanced for volatile reactions. Hydrogen-rich radicals and radical fragments from volatiles are beneficial to “spatiotemporal matching” under the synergistic effect of high fractal dimensions and well-dispersed Ni active sites within the carbon skeleton. Consequently, the yield of light oil could increase by 1.71 wt%, while the coke yield decreased by 0.32 wt% compared to inert quartz beads. Also, coke in tar (Coke-T) was rich in 3–5 cyclic aromatics structures with more carbon defects. Conversely, other Ni-modified carbon materials intensified the condensation reactions of volatiles due to the strong catalytic cracking performances of the surface-loaded Ni, oxygen-containing functional groups, and carbon structural defects. As a result, some volatiles were converted to gas and coke, and the resultant Coke-T contained more ordered carbon structures with poorer combustion reactivity.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134775"},"PeriodicalIF":6.7,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Optimizing the support morphology to boost ultra-deep hydrodesulfurization of diesel over NiMo/Al2O3 catalysts

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-27 DOI: 10.1016/j.fuel.2025.134844

Yitong Sun , Wenwen Ma , Ke Yu , Dong Li , Weiming Kong , Lian Kong , Zhen Zhao

The implementation of a modulated support structure represents an effective strategy for improving the performance of hydrodesulfurization (HDS) over supported catalysts. This study synthesized mesoporous Al₂O₃ supports with dandelion-like (DD) and nanoparticle aggregate (NP) morphologies, which were subsequently used as supports for the preparation of NiMo/Al₂O₃-DD and NiMo/Al₂O₃-NP catalysts. The catalytic properties of these catalysts were evaluated using dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) as model probe molecules. The structure and physicochemical properties of Al₂O₃ and NiMo/Al₂O₃ catalysts with different morphologies were comprehensively characterized using various characterization techniques. The experimental results demonstrate that, despite the similar specific surface area of the synthesized catalysts, their morphology significantly influenced the HDS performance. NiMo/Al₂O₃-DD catalyst exhibited the highest conversions of DBT and 4,6-DMDBT across all weight hourly space velocities (WHSV). The DBT conversion over NiMo/Al₂O₃-DD catalyst reached an impressive 99.6% under the reaction conditions of 340 ℃, 4.0 MPa and 10 h⁻¹, while the 4,6-DMDBT conversion achieved a remarkable value of 96.6 %. The enhanced catalytic performance can be attributed to the modifications in both the catalyst structure and surface properties induced by its morphology, thereby effectively regulating the interaction between metal and support (MSI), acidity, dispersion, and the accumulation morphology of NiMoS active phase.

{"title":"Optimizing the support morphology to boost ultra-deep hydrodesulfurization of diesel over NiMo/Al2O3 catalysts","authors":"Yitong Sun , Wenwen Ma , Ke Yu , Dong Li , Weiming Kong , Lian Kong , Zhen Zhao","doi":"10.1016/j.fuel.2025.134844","DOIUrl":"10.1016/j.fuel.2025.134844","url":null,"abstract":"<div><div>The implementation of a modulated support structure represents an effective strategy for improving the performance of hydrodesulfurization (HDS) over supported catalysts. This study synthesized mesoporous Al<sub>2</sub>O<sub>3</sub> supports with dandelion-like (DD) and nanoparticle aggregate (NP) morphologies, which were subsequently used as supports for the preparation of NiMo/Al<sub>2</sub>O<sub>3</sub>-DD and NiMo/Al<sub>2</sub>O<sub>3</sub>-NP catalysts. The catalytic properties of these catalysts were evaluated using dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) as model probe molecules. The structure and physicochemical properties of Al<sub>2</sub>O<sub>3</sub> and NiMo/Al<sub>2</sub>O<sub>3</sub> catalysts with different morphologies were comprehensively characterized using various characterization techniques. The experimental results demonstrate that, despite the similar specific surface area of the synthesized catalysts, their morphology significantly influenced the HDS performance. NiMo/Al<sub>2</sub>O<sub>3</sub>-DD catalyst exhibited the highest conversions of DBT and 4,6-DMDBT across all weight hourly space velocities (WHSV). The DBT conversion over NiMo/Al<sub>2</sub>O<sub>3</sub>-DD catalyst reached an impressive 99.6% under the reaction conditions of 340 ℃, 4.0 MPa and 10 h<sup>−1</sup>, while the 4,6-DMDBT conversion achieved a remarkable value of 96.6 %. The enhanced catalytic performance can be attributed to the modifications in both the catalyst structure and surface properties induced by its morphology, thereby effectively regulating the interaction between metal and support (MSI), acidity, dispersion, and the accumulation morphology of NiMoS active phase.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134844"},"PeriodicalIF":6.7,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Experimental investigation of prechamber enabled mixing-controlled combustion with natural gas – A pathway to ultra-low methane emissions

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2025-02-27 DOI: 10.1016/j.fuel.2025.134757

John Ronsman, John Valla, Osama Nsaif, Adam Dempsey

With increasing focus on the global climate crisis, there is strong interest in exploring ways to decarbonize many industries. Natural gas reciprocating engines are used for power generation, gas compression, and pipeline transmission. Due to its low reactivity, most natural gas engines today are premixed lean burn spark ignited (SI) engines. These engines produce criteria pollutants, such as nitrogen oxides (NOx) and carbon monoxide (CO), but due to their premixed nature, also produce relatively large amounts of unburned methane (CH₄) emissions. This study explores advanced combustion strategies for natural gas engines, particularly focusing on prechamber enabled mixing-controlled combustion (PCMCC), aiming to enhance performance and reduce methane emissions in large-bore natural gas engines. PCMCC uses an actively fueled prechamber to ignite direct injected natural gas, resulting in a non-premixed mixing-controlled combustion event that dramatically reduces methane emissions. Single-cylinder engine experiments were conducted to compare current premixed spark ignition technology and the PCMCC concept. PCMCC with natural gas fuel can achieve a consistent ∼ 75 % to 99 % reduction in methane emissions over a wide range of NOx emission levels. With the use of internal EGR, PC MCC NOx emissions were reduced to ∼ 1 g/kW-hr, which is similar to current engine technology, while maintaining ultra-low methane slip of ∼ 0.1 g/kW-hr, which is ∼ 99 % lower than current engine technology. Both concepts deliver equal gross indicated thermal efficiencies at similar compression ratios. However, due to its non-premixed nature, PCMCC operates without the fear of knock or preignition, and thus can operate at higher compression ratios providing an advantage in thermal efficiency compared to its premixed spark ignition counterpart. This study shows that PCMCC has potential to be a disruptive natural gas engine technology to dramatically reduce methane emissions, and thus greenhouse gas emissions, in the near term.

{"title":"Experimental investigation of prechamber enabled mixing-controlled combustion with natural gas – A pathway to ultra-low methane emissions","authors":"John Ronsman, John Valla, Osama Nsaif, Adam Dempsey","doi":"10.1016/j.fuel.2025.134757","DOIUrl":"10.1016/j.fuel.2025.134757","url":null,"abstract":"<div><div>With increasing focus on the global climate crisis, there is strong interest in exploring ways to decarbonize many industries. Natural gas reciprocating engines are used for power generation, gas compression, and pipeline transmission. Due to its low reactivity, most natural gas engines today are premixed lean burn spark ignited (SI) engines. These engines produce criteria pollutants, such as nitrogen oxides (NOx) and carbon monoxide (CO), but due to their premixed nature, also produce relatively large amounts of unburned methane (CH<sub>4</sub>) emissions. This study explores advanced combustion strategies for natural gas engines, particularly focusing on prechamber enabled mixing-controlled combustion (PCMCC), aiming to enhance performance and reduce methane emissions in large-bore natural gas engines. PCMCC uses an actively fueled prechamber to ignite direct injected natural gas, resulting in a non-premixed mixing-controlled combustion event that dramatically reduces methane emissions. Single-cylinder engine experiments were conducted to compare current premixed spark ignition technology and the PCMCC concept. PCMCC with natural gas fuel can achieve a consistent ∼ 75 % to 99 % reduction in methane emissions over a wide range of NOx emission levels. With the use of internal EGR, PC MCC NOx emissions were reduced to ∼ 1 g/kW-hr, which is similar to current engine technology, while maintaining ultra-low methane slip of ∼ 0.1 g/kW-hr, which is ∼ 99 % lower than current engine technology. Both concepts deliver equal gross indicated thermal efficiencies at similar compression ratios. However, due to its non-premixed nature, PCMCC operates without the fear of knock or preignition, and thus can operate at higher compression ratios providing an advantage in thermal efficiency compared to its premixed spark ignition counterpart. This study shows that PCMCC has potential to be a disruptive natural gas engine technology to dramatically reduce methane emissions, and thus greenhouse gas emissions, in the near term.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"392 ","pages":"Article 134757"},"PeriodicalIF":6.7,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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