Fuel最新文献

{"title":"Water and citric acid solubilization of potassium components in biomass combustion ash by kaolin addition","authors":"Fandi Angga Prasetya ,&nbsp;Sawa Ishizuka ,&nbsp;Tomonori Fukasawa ,&nbsp;Toru Ishigami ,&nbsp;Kazuyuki Sakemi ,&nbsp;Takako Fukuda ,&nbsp;Kunihiro Fukui","doi":"10.1016/j.fuel.2025.136419","DOIUrl":"10.1016/j.fuel.2025.136419","url":null,"abstract":"<div><div>The use of biomass combustion ash as potassium fertilizer is limited by its insoluble potassium components. This study proposes a novel method to enhance the soluble potassium content in biomass ash by transforming insoluble potassium into soluble forms. The investigation applied heat treatment on insoluble potassium at 700–950 °C, including mixtures of silica, K₂CO_3, and kaolin as a reagent. Notably, adding kaolin raised the reaction temperature between SiO₂ and K₂CO₃ from 824.3 to 876.6 °C. At 950 °C, a 12 % decrease in water-soluble and a 50 % increase in citric acid-soluble potassium confirmed successful conversion. Presence of kaolin effectively inhibited formation of poorly soluble K₂SiO₃, promoting instead the more soluble cubic leucite phase, led to shift the insoluble to soluble potassium components. Further heat treatment of biomass ash with kaolin at 1000 °C showed increased citric acid-soluble potassium and decreased water-soluble forms, supported by changes in leucite-to-SiO₂ crystal peak ratios, which became more pronounced with higher kaolin content, confirming kaolin’s role in shifting potassium solubility. In addition, acid treated- kaolin boosted the conversion from insoluble- to soluble- K components.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136419"},"PeriodicalIF":7.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750780","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}

{"title":"Thermal and chemical analysis on the hydrogen heterogeneous reaction characteristics in a catalytic micro-combustor with blunt body","authors":"Qingbo Lu ,&nbsp;Shijia Ding ,&nbsp;Yi Zhang ,&nbsp;Yunchao Wang ,&nbsp;Baowei Fan ,&nbsp;Muhammad Nauman ,&nbsp;Wenming Yang ,&nbsp;Jianfeng Pan","doi":"10.1016/j.fuel.2025.136384","DOIUrl":"10.1016/j.fuel.2025.136384","url":null,"abstract":"<div><div>The effects of a blunt body on the heterogeneous reaction (HTR) characteristics of premixed hydrogen/air in a catalytic micro-combustor are investigated by numerical simulation. A two-dimensional Computational Fluid Dynamics (CFD) model incorporating a detailed surface reaction mechanism of hydrogen over platinum (Pt) is employed and validated against experimental data. The connection between the hydrogen HTR and the associated heat and mass transfer processes in the presence of a near-wall vortex induced by blunt body within the microchannel are discussed by thermal and chemical analysis. Numerical results show that a counterclockwise near-wall vortex is observed approximately 4.5 to 6.5 mm downstream of the inlet at a blockage ratio of 0.8. The distributions of temperature, key species concentration, and reaction rates indicate that the presence of the near-wall vortex enhances reactant transport to the catalytic surface, leading to accelerated HTR kinetics. The near-wall vortex significantly influences the overall reaction by promoting the downstream removal of products accumulated near the blunt body and conveys reactants and free radicals toward the catalytic surface. And the near-wall vortex ensures a more uniform distribution of heat generated by catalytic walls, restoring heat transfer performance. The skin friction coefficient (C_f) and Stanton number (S_t) are enhanced within the near-wall vortex region. The presence of near-wall vortices significantly improves fluid mixing and heat/mass transfer within the catalytic channel, thereby promoting hydrogen conversion ratio. These findings offer valuable insights into advancing catalytic combustion efficiency and guiding the design of vortex-enhanced micro catalytic combustors suited for extreme operating environments.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136384"},"PeriodicalIF":7.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750778","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}

{"title":"Study of deformation and fragmentation of emulsion under electric field and shear based on fluid dynamics","authors":"Chuanke Liang,&nbsp;Zexin Liu,&nbsp;Sichen Wei,&nbsp;Nanjun Ma,&nbsp;Qijie Sun,&nbsp;Tao Li","doi":"10.1016/j.fuel.2025.136403","DOIUrl":"10.1016/j.fuel.2025.136403","url":null,"abstract":"<div><div>To address the demulsification challenges of crude oil emulsions, this study investigates the breakup characteristics of droplets in electric and flow fields based on fluid dynamics theory through numerical simulation. The findings reveal that droplets undergo deformation under the combined effects of surface tension and viscous or electric field forces. As the capillary number (Ca) increases, droplet deformation gradually intensifies. When the critical Ca is reached, the droplet undergoes viscous shear-induced breakup. The critical Ca is influenced by droplet size, continuous phase viscosity, and interfacial tension coefficient. Similarly, as the electric capillary number (<span><math><mrow><msub><mtext>Ca</mtext><mtext>E</mtext></msub></mrow></math></span>) increases, the droplet deformation grows. Upon reaching the critical <span><math><mrow><msub><mtext>Ca</mtext><mtext>E</mtext></msub></mrow></math></span>, tip-induced breakup occurs. The critical <span><math><mrow><msub><mtext>Ca</mtext><mtext>E</mtext></msub></mrow></math></span> is determined by droplet size and interfacial tension coefficient. This study derives the functional expressions for the critical capillary number (Ca<span><math><mrow><mo>′</mo></mrow></math></span>) and critical electric capillary number (<span><math><mrow><msub><mtext>Ca</mtext><mtext>E</mtext></msub><mo>′</mo></mrow></math></span>) for viscous shear-induced and electric field-induced breakups, respectively. Finally, a droplet size distribution model is established using these expressions, further validating the accuracy of the critical Ca and the critical <span><math><mrow><msub><mtext>Ca</mtext><mtext>E</mtext></msub></mrow></math></span> expressions, providing theoretical support for the efficient demulsification of complex emulsions in engineering applications.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136403"},"PeriodicalIF":7.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750284","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}

{"title":"A synergistic catalyst of Fe/ZSM-5 for robust aromatics production via methane dehydroaromatization","authors":"Xiaohui Wang,&nbsp;Zhilong Cheng,&nbsp;Bingrong Liu,&nbsp;Huiyi Liu,&nbsp;Xin Fang,&nbsp;Ruiqi Chai,&nbsp;Lishuang Ma,&nbsp;Yuchao Lyu,&nbsp;Jianye Fu,&nbsp;Xinmei Liu","doi":"10.1016/j.fuel.2025.136325","DOIUrl":"10.1016/j.fuel.2025.136325","url":null,"abstract":"<div><div>Methane dehydroaromatization (MDA) was a promising technology for the synthesis of high value-added aromatics through natural gas. Fe/ZSM-5 catalysts were widely used in MDA reaction. However, its catalytic mechanism remained ambiguous. In this work, a novel one-pot strategy was developed for the preparation of Fe/ZSM-5 catalysts, which can delicately control the iron species and acidic property of Fe/ZSM-5 catalysts. In-situ DRIFTS and DFT calculation demonstrated that MDA followed a bifunctional mechanism and the second C–H bond breaking process of CH₄ was the rate-determining step, where methane underwent coupling and dehydrogenation at the iron active sites to generate intermediate species (ethylene), and Brønsted acid sites played a key role in determining the selectivity of aromatics. Moreover, CO-pulse chemisorption revealed the quantitative synergistic effect between metal active sites and Brønsted acid sites. Catalysts with highly dispersed iron oxide and proper density of Brønsted acid sites exhibited the best catalytic performance. This study elucidated the catalytic roles of iron species and Brønsted acid sites in Fe/ZSM-5 catalysts in MDA and provided guidance for the future development of highly active MDA catalysts.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136325"},"PeriodicalIF":7.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750775","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}

{"title":"Effects of oxygen concentration and PdOx on NOx desorption from Pd-CHA","authors":"Takeshi Ohtsu ,&nbsp;Shohei Washiyama ,&nbsp;Nao Tsunoji ,&nbsp;Akira Oda ,&nbsp;Atsushi Satsuma","doi":"10.1016/j.fuel.2025.136391","DOIUrl":"10.1016/j.fuel.2025.136391","url":null,"abstract":"<div><div>A passive NOx adsorber effectively suppresses NOx emissions from automotive exhaust below 200 °C. In this study, we investigate how the NOx desorption behavior of Pd-loaded CHA (Pd-CHA) catalysts is influenced by the O₂ partial pressure and the dispersion state of Pd. When Pd exists predominantly as isolated cations, the partial pressure of O₂ does not affect the NOx desorption temperature. In contrast, Pd-CHA containing PdOx shows a pronounced shift of NOx desorption toward lower desorption temperatures. In-situ IR spectra shows that PdOx oxidizes adsorbed nitrosyl species to nitrate, which desorbs more readily at lower temperatures, contributing to the lower NOx desorption temperature. The present findings suggest that optimizing the PdOx content and O₂ partial pressure enables the release of trapped NOx to synchronize with the active window of downstream NH₃-SCR catalysts, thereby enhancing low-temperature NOx conversion and mitigating cold-start emissions.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136391"},"PeriodicalIF":7.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750779","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}

{"title":"Critical nanoparticle formation in iron combustion: single particle experiments with in-situ multi-parameter diagnostics aided by multi-scale simulations","authors":"Tao Li ,&nbsp;Bich-Diep Nguyen ,&nbsp;Yawei Gao ,&nbsp;Leon Elsässer ,&nbsp;Daoguan Ning ,&nbsp;Arne Scholtissek ,&nbsp;Adri C.T. van Duin ,&nbsp;Christian Hasse ,&nbsp;Benjamin Böhm","doi":"10.1016/j.fuel.2025.136303","DOIUrl":"10.1016/j.fuel.2025.136303","url":null,"abstract":"<div><div>In practical iron combustion systems, the formation of iron oxide nanoparticles (NP) presents challenges such as efficiency penalties and fine dust emissions, necessitating a deeper understanding of the underlying formation mechanisms and critical thermochemical conditions. This study, utilizing both experiments and multi-scale simulation tools, investigates the NP clouds generated by single iron particles burning in high-temperature oxidizing environments. The ambient gas conditions were provided by a laminar flat flame burner, where the post-flame oxygen mole fraction was varied between 20, 30, and 40 vol%, with a constant gas temperature of approximately 1800 K. In the experiments, high-speed <em>in-situ</em> diagnostics were employed to simultaneously measure particle size, NP release onset, NP cloud evolution, and the surface temperature history of the microparticles. The setup involved three 10 kHz imaging systems: one for two-color pyrometry and two for diffuse backlight-illumination (DBI), specifically targeting microparticle size and nanoparticle cloud measurements. The study demonstrates the powerful capabilities of these multi-physics diagnostics, allowing for precise quantification of NP release onset time and temperature, which were found to depend on both particle size and ambient oxygen mole fractions. Detailed CFD simulations revealed that the enhanced convection velocity, driven by increased Stefan flow, transports NPs towards the parent iron particles, particularly under high-oxygen conditions. This phenomenon delayed the appearance of detectable NP clouds, leading to higher apparent microparticle temperatures at the onset of NP release. This insight complemented the experimental observations, providing a more comprehensive understanding of the observed NP-cloud release temperature that increases with higher oxygen levels. Further analysis through molecular dynamics (MD) simulations uncovered potential reaction pathways of precursor formation and nanoparticle agglomeration. The MD simulations showed that the initial temperature significantly influenced the amount of gas-phase precursors and subsequently the composition of the resulting nanoclusters, with Fe(II) predominating at higher temperatures and Fe(III) at lower temperatures. This integrated approach combining experiments and numerical analysis not only advances our understanding of NP formation in iron combustion but also provides valuable insights into the thermochemical conditions that dominate nanoparticle characteristics.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136303"},"PeriodicalIF":7.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750285","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}

{"title":"Structure–tuned, phosphorus–doped hierarchical porous biochar via green hydrothermal carbonization and activation for formaldehyde adsorption","authors":"Bochong Sun,&nbsp;Mingshu Chi,&nbsp;Li Bai,&nbsp;Jiankai Liu,&nbsp;Xiaoyu Wen","doi":"10.1016/j.fuel.2025.136381","DOIUrl":"10.1016/j.fuel.2025.136381","url":null,"abstract":"<div><div>Carbonaceous adsorbents synthesized through traditional methods often suffer from inherent limitations, such as restricted porosity, homogeneous pore distribution, and insufficient surface functional groups, which collectively constrain their formaldehyde (HCHO) adsorption capabilities. To overcome these shortcomings, this study proposes a straightforward and efficient two-stage strategy to fabricate biochar-based adsorbents. In particular, phosphorus-doped porous carbons (MBPs) were successfully synthesized using cypress sawdust as a biomass precursor through phosphoric acid (H₃PO₄)-assisted hydrothermal carbonization (HTC), followed by KOH activation. Among the prepared samples, MBP2-240-A exhibited the highest specific surface area (1889.0 m²/g) and a micropore volume of 0.70 cm³/g, forming a hierarchical pore network that synergizes micropores and mesopores while offering abundant active adsorption sites. XPS and FTIR characterization confirmed the successful introduction of surface functional groups, such as P–O, P=O, and C–P, which enhanced the surface polarity of the carbon matrix and contributed to improved chemical adsorption capacity. Additionally, the subsequent KOH activation process further refined the pore structure and introduced additional oxygen-containing functional groups, significantly enhancing the overall adsorption performance. As a result of these synergistic effects, MBP2-240-A exhibited exceptional dynamic HCHO adsorption performance, achieving a maximum adsorption capacity of 8.75 mmol/g. Through the integration of dynamic adsorption testing and Grand Canonical Monte Carlo (GCMC) simulations, the configuration regulation of phosphorus-doped hierarchically porous biochar was systematically elucidated, providing valuable theoretical insights and practical foundations for the future design and optimization of high-efficiency HCHO adsorbent materials.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136381"},"PeriodicalIF":7.5,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750782","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}

{"title":"CO2 adsorption behavior and characterization model on inorganic mineral pore surfaces: a molecular simulation study compared with organic pores","authors":"Feng Miao ,&nbsp;Jinzhang Jia ,&nbsp;Xintong Chen ,&nbsp;Haiting Lu ,&nbsp;Xueying Liu ,&nbsp;Yuying Tu ,&nbsp;Di Wu","doi":"10.1016/j.fuel.2025.136415","DOIUrl":"10.1016/j.fuel.2025.136415","url":null,"abstract":"<div><div>Shale reservoirs contain not only abundant organic nanopores but also a large number of inorganic nanopores, both of which play crucial roles in CO₂ adsorption. In this study, the adsorption behavior of CO₂ on the surfaces of various inorganic minerals and organic pores is investigated using grand canonical Monte Carlo (GCMC) molecular simulations. A multilayer adsorption model is developed based on the Ono–Kondo lattice (OK) model, incorporating van der Waals and electrostatic interactions for characterizing solid–gas interactions. Simulation results reveal that both organic and inorganic pore surfaces exhibit distinctive multilayer adsorption characteristics. Under low-pressure conditions, inorganic minerals demonstrate significantly stronger CO₂ adsorption capacities compared to organic pores. Specifically, the adsorption capacity follows the order: montmorillonite (MMT) &gt; calcite &gt; illite–MMT mixed layers &gt; organic pores &gt; quartz. On inorganic mineral surfaces, CO₂ adsorption is influenced by both van der Waals and electrostatic interactions, with the latter dominating in the first adsorption layer near the pore wall. After calibrating the OK model using molecular simulation data, we found that the CO₂ density distribution across adsorption layers is accurately reproduced and shows strong agreement with GCMC results. These findings provide a solid theoretical basis for quantifying absolute adsorption and offer valuable insights into the role of pore structure heterogeneity in CO₂ sequestration in shale reservoirs.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136415"},"PeriodicalIF":7.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144738604","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}

{"title":"Oil sludge from an environmentally hazardous pollutant to an efficient source for energy production via thermal/ catalytic pyrolysis routes","authors":"Mohamed N.A. Mahmoud ,&nbsp;Esraa M. El-Fawal ,&nbsp;Ahmed M.A. El Naggar ,&nbsp;Asmaa I. Zahran ,&nbsp;Hussien A. El Sayed ,&nbsp;Islam M. El-Sewify ,&nbsp;Bassem H. Heakal ,&nbsp;Mostafa M.H. Khalil","doi":"10.1016/j.fuel.2025.136367","DOIUrl":"10.1016/j.fuel.2025.136367","url":null,"abstract":"<div><div>Oil sludge, a hazardous waste from petroleum operations, poses severe environmental threats when improperly managed. This study presents a comprehensive approach to convert oil sludge into clean fuel gases, mainly liquefied petroleum gas (LPG) and natural gas (NG), using thermal and catalytic pyrolysis. Three nanocomposite catalysts (NiO-MoO₃/Al₂O₃, MgO-MoO₃/Al₂O₃, and MgO-NiO/Al₂O₃) were synthesized via co-precipitation. The featured characterizations of these three composites were determined using X-ray diffection (XRD), scanning electron microscopy (SEM), BET surface area analysis, energetic Dispersive X-Ray (EDX), and thermal gravimetric analysis (TGA). Textural results showed respective surface area values of 71.2, 204.2, and 213.7 m²/g, observing the highest porosity and thermal stability for MgO-NiO/Al₂O₃. Thermal pyrolysis (in absence of catalyst) at 300 °C for 1.5 h under pressure (5 bar N₂) achieved a maximum oil sludge-to-gas conversion of 53.7 wt%, where (NG)components represented nearly 909 vol% of content in the produced gas. In contrast, catalytic pyrolysis (under similar conditions) could significantly improve the outcomes of oil sludge transformation into energy soutces. The most effective catalyst, MgO-NiO/Al₂O₃, achieved a conversion wt % of 77.1 and NG concentration of 96 vol% (at 300 °C for 1.5 h under 5 bar N₂). On the other side, NiO-MoO₃/Al₂O₃ converted 66 wt% of OS into gases while MgO-MoO₃/Al₂O₃ gave conversion percentage of 64.5, under similar conditions. The noted results confirm that pressurized catalytic pyrolysis, using mesoporous alumina-based nanocomposites, enhances the yield of fuel gases and their quality, proving efficient conversion of oil sludge into high-calorific value and carbon–neutral fuels.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136367"},"PeriodicalIF":7.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750776","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}

{"title":"Optimizing the degree of structural disorder in coal-based porous carbon for enhancing supercapacitor capacitance performance","authors":"Wanqing Li ,&nbsp;Xiaoqin Yang ,&nbsp;Chao Yuan ,&nbsp;Xian Wang ,&nbsp;Xuejian Huo ,&nbsp;Yan Ye ,&nbsp;Zitan Qian ,&nbsp;Zhihong Qin","doi":"10.1016/j.fuel.2025.136378","DOIUrl":"10.1016/j.fuel.2025.136378","url":null,"abstract":"<div><div>Pore size is often regarded as a crucial factor in enhancing the electrochemical performance of supercapacitors. However, we have found that the degree of structural disorder in porous carbon exhibits a stronger correlation with the specific capacitance. Herein, K₂CO₃-assisted KOH activation of cleaned fat coal was employed to precisely regulate structural disorder, simply by adjusting the K₂CO₃ addition amount. This structural transformation is primarily attributed to the variations of alkali concentration and the eutectic point in the mixed activation system, thereby influencing the generation of reactive oxygen species which prevent the assembly of graphite microcrystalline domains. The most disordered structure of the optimal porous carbon PC-14 allows it to attain both an ultra-high specific surface area (3710.92 m²/g) and a high specific capacitance simultaneously. The assembled supercapacitor demonstrates a specific capacitance of 313.34 F/g at 0.5 A/g. After 20,000 cycles at 10 A/g, the capacity retention remains at 101.36 %, with an energy density of 10.72 Wh/kg at a power density of 124.07 W/kg. The elucidated activation mechanism of mixed activation systems facilitates the adjustment of the microcrystalline structure of coal-based porous carbons, which gives an important guide for the preparation of coal-based carbon materials.</div></div>","PeriodicalId":325,"journal":{"name":"Fuel","volume":"404 ","pages":"Article 136378"},"PeriodicalIF":7.5,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144738605","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}