Journal of The Energy Institute最新文献

{"title":"Heavy metal speciation in bottom slags from the co-combustion of municipal sludge and organic medical solid waste","authors":"Binbin Yao ,&nbsp;Junwei Shen ,&nbsp;Junping Meng ,&nbsp;Jinsheng Liang","doi":"10.1016/j.joei.2025.102321","DOIUrl":"10.1016/j.joei.2025.102321","url":null,"abstract":"<div><div>Heavy metal toxicity in bottom slags constitutes a major challenge limiting their reutilization. This study collected bottom slag from co-combustion experiments of municipal sludge (MS) and organic medical solid waste (OMSW) at various ratios in a tubular furnace, followed by analysis of Cr, Ni, Cu, and Zn concentrations. The European Community Bureau of Reference (BCR) sequential extraction method was used to analyze the speciation characteristics of the heavy metals, and the chemical speciation of Cr, Ni, and Cu in the bottom slag at 700 °C and 850 °C was dominated by the residual state, which accounted for 57.20–77.25 % of the heavy metals. When the reaction temperature reached 1000 °C, the proportion of the reducible state of Cr was most obviously elevated, accounting for 35.86–59.07 %, and the proportion of the acid soluble state of Zn was the highest, accounting for more than 46.65 %. Thermodynamic analysis via HSC Chemistry 6.0 demonstrated that increasing the temperature increased the reactions of the four heavy metals with iron to form the corresponding ferrate salts, explaining the increased proportion of the reducible state at 1000 °C. The Hakanson potential ecological hazard index method was used to evaluate the ecological risk of heavy metals. The highest value of the individual pollution factor of Zn reached a high risk, while the pollution levels of Cr, Ni, and Cu were all under elevated risk. The comprehensive potential ecological risk value of the heavy metals in the bottom slag at 1000 °C was the highest, and the pollution levels of the four heavy metals were Cu, Ni, Cr, and Zn in descending order.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102321"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220202","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}

{"title":"Molecular insights into the synergistic effect of co-pyrolysis of low-rank coal and cellulose: Atomic tracking and labeling, interaction mechanisms, and kinetics","authors":"Jie Wang ,&nbsp;Wei Wang ,&nbsp;Xuheng Chen ,&nbsp;Kui Zheng ,&nbsp;Runsheng Xu","doi":"10.1016/j.joei.2025.102317","DOIUrl":"10.1016/j.joei.2025.102317","url":null,"abstract":"<div><div>Understanding the synergistic mechanisms between pyrolysis products is crucial for optimizing coal-biomass co-pyrolysis technology. However, the underlying microscopic mechanisms involving complex intermolecular interactions and coupled reaction pathways remain unclear, significantly limiting precise regulation of the process. Hence, this study proposes an atom-tracking and labeling strategy, employing ReaxFF MD simulations to elucidate the structural interactions and synergistic transformation mechanisms between cellulose and low-rank coal during co-pyrolysis. Results show cellulose fragments enhance char yield via crosslinking with coal molecule, while simultaneously inhibiting further polymerization into larger char structures. Moreover, the co-pyrolysis process exhibits a significant synergistic dehydrogenation effect. The generated H radicals recombine to form H₂, while attacking oxygenated functional groups in coal to increase gas yield. This contributes to a lower-energy reaction pathway for coal decomposition, resulting in a 24.6 % reduction in the apparent activation energy of coal pyrolysis. The strongest synergistic effects are observed in the 2600–2800 K temperature range. Experimentally determining this temperature range can serve as a critical window for optimizing process parameters in industrial production. This study offers new insights into the synergistic effects of coal-biomass co-pyrolysis and provides a methodological inspiration for analyzing interactions in complex systems.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102317"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220204","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}

{"title":"Experimental research on the hydrotreatment of waste tire pyrolysis oil upgrading with CoMo/Al2O3 catalyst","authors":"Penglin Ma ,&nbsp;Zengyi Ma ,&nbsp;Jianhua Yan ,&nbsp;Yike Zhang ,&nbsp;Qunxing Huang","doi":"10.1016/j.joei.2025.102329","DOIUrl":"10.1016/j.joei.2025.102329","url":null,"abstract":"<div><div>Waste tire pyrolysis oil (WTPO) exhibits high calorific value but requires heteroatoms (S/N) and polycyclic aromatic hydrocarbons (PAHs) reduction for fuel applications. Hydrotreatment is an effective method for removing these heteroatoms, enhancing hydrocarbon saturation, and improving oil quality. This study compares unpresulfurised CoMo/Al₂O₃ catalytic versus non-catalytic hydrotreatment to upgrade WTPO. The research systematically explores the transformation of sulfur- and nitrogen-containing compounds, as well as hydrocarbons, under various reaction conditions. The difficulty of hydrogenation desulfurization for four types of sulfur-containing compounds was ranked. C–N bonds in linear compounds and heterocycles in nitrogen-containing compounds can break under the influence of a catalyst or at elevated temperatures and pressures. However, the direct elimination of nitrogen atoms bonded to the benzene ring in aniline-like compounds remains challenging using this catalyst. A representative heterocyclic compound containing both nitrogen and sulfur, benzothiazole, underwent ring-opening conversion to aniline. Even when using unpresulfurized catalysts at higher weight hourly space velocity (WHSV), dehydrogenation side reactions and PAHs formation can be suppressed to a certain extent. Based on these findings, this paper offers useful insights into the catalytic performance of CoMo/Al₂O₃ during WTPO hydrotreatment and provides practical references for catalyst selection and reaction condition optimization.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102329"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145266504","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}

{"title":"Recycling of waste lithium-ion battery cathode materials to synthesize nickel-cobalt-manganese catalysts for efficient CO2 straw gasification","authors":"Jiahui Li,&nbsp;Mingyu Ma,&nbsp;Juan Wu,&nbsp;Guien Zhou,&nbsp;Yingdi Xu,&nbsp;Muzamil Ali Brohi,&nbsp;Dengxin Li,&nbsp;Wenjing Sang,&nbsp;Shihong Xu","doi":"10.1016/j.joei.2025.102327","DOIUrl":"10.1016/j.joei.2025.102327","url":null,"abstract":"<div><div>Driven by carbon neutrality goals, the application of carbon dioxide gasification technology has demonstrated significant environmental and economic benefits. This study utilized waste lithium-ion battery cathode materials (LiNi_0.5Co_0.2Mn_0.3, LiCoO₂, LiMn₂O₄) to synthesize highly efficient nickel-cobalt-manganese catalysts for carbon dioxide-assisted straw gasification. Gasification experiments were conducted using a laboratory-scale fixed-bed gasification reactor, and the evolution of the catalyst's structure and physicochemical properties were investigated using characterization methods such as XRD, XPS, SEM, and TGA. The results showed that the catalyst prepared using LiNi_0.5Co_0.2Mn_0.3 as raw material increased the synthesis gas yield to 747.80 mL/g, representing a 134 % increase compared to the control group without catalyst addition; After adjusting the cobalt content to 40 % using LiCoO₂, the synthesis gas yield further increased to 865.24 mL/g, while tar production decreased significantly by 84 % to 4.4 wt%, and activity only declined by 23.3 % after ten cycles. Its outstanding performance stems from the synergistic interaction of Ni, Co, and Mn: nickel promotes carbon dioxide decomposition, cobalt enhances electron conduction, and manganese stabilizes the framework structure. Optimizing cobalt content facilitates C–C bond cleavage and the Boudouard reaction, thereby enhancing tar cracking and carbon monoxide production, and effectively inhibits methane formation through Ni-Co-Mn synergistic reforming. This study establishes a closed-loop “waste battery-catalyst-biomass gasification” strategy, which enables the recycling of waste lithium batteries and the efficient production of synthesis gas, providing a reference for industrial application of high-value utilization of waste lithium batteries and catalytic biomass gasification.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102327"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145266508","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}

{"title":"Decoding fuels and oxygen carriers interaction: Insights into site-specific adsorption mechanisms and driving forces of H2, CH4 and CO on doped iron-based oxygen carriers during chemical looping combustion","authors":"Jinpeng Zhang ,&nbsp;Liangliang Meng ,&nbsp;Huining Wan ,&nbsp;Jieying Jing ,&nbsp;Yurong He ,&nbsp;Yuhua Wu ,&nbsp;Jianbo Wu ,&nbsp;Hui Zhang ,&nbsp;Hongcun Bai","doi":"10.1016/j.joei.2025.102326","DOIUrl":"10.1016/j.joei.2025.102326","url":null,"abstract":"<div><div>Oxygen carriers (OCs) in chemical looping combustion (CLC) system can catalyze fuel decomposition and regulate the reactions kinetics. Adsorption of gaseous fuel on the surface of the OCs during CLC is of vital importance, as the core of catalytic reactions begins with the adsorption mechanism and even largely determines the enrichment, activation and selectivity of the reactants. However, the iron-based OCs with transition metal doping made minute structural differences could be largely divergent in the adsorption behavior during CLC, which seems not to raise much concern. Herein, the surface interactions for adsorption of representative gaseous fuels, H₂, CH₄, and CO onto Mn/Co/Ni/Cu/Zn-doped iron-based OCs during CLC were explored in-depth based on DFT calculations. The nature of the interaction between fuels and OCs was revealed from both quantitative views and direct pictures. Stable adsorption configurations were identified. H₂ and CO prefer bridge sites, while CH₄ favors hollow sites. Energy decomposition analysis quantitatively revealed distinct dominant interactions: orbital forces (55–65 %) for H₂, electrostatic interactions (40–50 %) for CH₄, and orbital forces for CO physisorption (45–57 %) versus combined orbital/electrostatic forces (50–56/42–49 %) for chemisorption. Reduced density gradient and interaction region indicator analyses visually confirmed van der Waals-dominated interactions, with Cu/Ni/Co doping enhancing adsorption. Electronic structure analysis (density of states, <em>d</em>-band center, work function) demonstrated that doping modulates OCs reactivity via TM···O/Fe···O interactions, upward <em>d</em>-band shifts, and reduced work functions, driven by dopant electronic structure, surface charge imbalance, and lattice distortion.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102326"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220079","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}

{"title":"Evaluating methane substitution by NH3/H2/C3H8 blends in premixed combustion: Feasibility assessment through laminar burning velocity, flame instability and combustion efficiency","authors":"Jiao Chen ,&nbsp;Haoxin Deng ,&nbsp;Xunxian Shi ,&nbsp;Chenglong Yu ,&nbsp;Jun Song ,&nbsp;Qifeng Zhu ,&nbsp;Guoyan Chen ,&nbsp;Xuegui Wang","doi":"10.1016/j.joei.2025.102318","DOIUrl":"10.1016/j.joei.2025.102318","url":null,"abstract":"<div><div>To support the low-carbon transition of energy systems, this study investigates the combustion characteristics of NH₃/H₂/C₃H₈ ternary blends with methane-equivalent calorific value using the spherical expanding flame method. The laminar burning velocity (LBV) can be adjusted to match methane via blend ratio design. As NH₃ volume increases from 0 to 0.712, LBV drops by over 66 %. The chemical and thermal effects were separated, and radiation effects were quantified. Key flame parameters, including Markstein length, expansion ratio, flame thickness, critical Peclet number, Karlovitz number, and dimensionless growth rate, were analyzed to evaluate the influence of fuel composition and equivalence ratio on flame propagation and stability. Higher NH₃ fractions improved flame stability. Methane interchangeability was assessed using the High Wobbe index and LBV. Results show that MECV-based NH₃/H₂/C₃H₈ blends offer good combustion performance and are promising low-carbon methane alternatives.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102318"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220082","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}

{"title":"Low-temperature 3D-Printed porous microreactors with magnetic induction heating for methanol steam reforming to hydrogen","authors":"Yi Zhang ,&nbsp;Wenming Guo ,&nbsp;Chenxu Guo ,&nbsp;Hang Qin ,&nbsp;Jiawei Xie ,&nbsp;Wen Xie ,&nbsp;Pengzhao Gao ,&nbsp;Hanning Xiao","doi":"10.1016/j.joei.2025.102312","DOIUrl":"10.1016/j.joei.2025.102312","url":null,"abstract":"<div><div>Methanol steam reforming (MSR) is considered one of the most promising hydrogen production technologies. However, MSR currently faces challenges such as low heat transfer efficiency in the reactor and suboptimal hydrogen production rates. To address these issues, this study proposes a method for fabricating low-temperature 3D-printed porous microreactors, exploring the effects of processing temperature and the use of silica sol with different pH values as a binder. Furthermore, the microreactor is integrated with a magnetic induction heating system, enabling real-time hydrogen production. This method ensures uniform catalyst distribution while overcoming the problem of excessive temperature differences between the support preparation and catalyst loading steps, which typically leads to catalyst accumulation on the surface of the support. Using neutral silica sol and a low-temperature treatment at 300 °C, the microreactor exhibited optimal catalytic performance. During the MSR process, the microreactor achieved complete methanol conversion at 260 °C with H₂ selectivity ranging from 76.9 % to 78.5 %, while maintaining low selectivity for CO (&lt;1.56 %) and CH₄ (&lt;0.08 %). Moreover, the microreactor demonstrated excellent stability and long-term performance, maintaining 88 % methanol conversion after 100 h of operation. This work addresses the temperature mismatch issue between catalyst loading and support preparation, providing new insights and methods for the practical application and industrialization of low-temperature, high-efficiency hydrogen production technologies.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102312"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220083","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}

{"title":"Machine learning integrated solvothermal liquefaction of lignocellulosic biomass to maximize bio-oil yield","authors":"Bulutcem Öcal,&nbsp;Hasan Sildir,&nbsp;Aslı Yüksel","doi":"10.1016/j.joei.2025.102310","DOIUrl":"10.1016/j.joei.2025.102310","url":null,"abstract":"<div><div>Accelerating consumption of limited fossil-based for economic growth and simultaneously mitigating greenhouse gas emissions create a dilemma that is waiting to be solved by researchers. In this context, solvothermal liquefaction of lignocellulosic biomass to produce bio-oil is a promising way to obtain green energy. However, maximizing bio-oil is challenging to optimize the operating parameters employing conventional techniques due to the complexity and non-linearity of the process. Lately, machine learning approaches have become powerful tools for addressing complex nonlinear problems by predicting process behavior and regulating operating parameters for optimization by learning from datasets. The current research demonstrates integrating experimental and a developed artificial neural network model to optimize solvothermal liquefaction of <em>pinus brutia</em>, based on temperature, water fraction, and biomass amount in maximizing bio-oil generation for the first time. The highest bio-oil yields were obtained at 31.40 %, 18.68 %, and 39.69 %, respectively, with 4 and 8 g biomass in the presence of water, ethanol, and water/ethanol mixture at 240 °C. Under the model conditions, the maximum bio-oil yield was experimentally verified at 46.20 %, which was predicted at 48.8 %. Beyond providing accurate yield predictions, the approach highlights the potential of date-driven modeling to reduce experimental workload and cost while aiding parameter selection to improve efficiency. These outcomes emphasize the importance of machine learning integration into liquefaction process, providing remarkable results for future process design, optimization, and scalability. On the other hand, the study also includes characterization results (ultimate, proximate, FTIR, and GC–MS) of selected products and <em>pinus brutia</em>.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102310"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220085","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}

{"title":"Degradation characteristics of the lignocellulosic biomass during alkaline oxidative fractionation using molecular oxygen under mild conditions","authors":"Jing-Xian Wang ,&nbsp;Xuan-Jie Zou ,&nbsp;Wen-Long Xu ,&nbsp;Biao Liang ,&nbsp;Yi-Nan Yang ,&nbsp;Zi-Hao Chen ,&nbsp;Bo-Yang Chen ,&nbsp;Da-Meng Wang ,&nbsp;Cheng-Biao Wang ,&nbsp;Pei-Jie Zong ,&nbsp;Ying-Yun Qiao ,&nbsp;Yuan-Yu Tian","doi":"10.1016/j.joei.2025.102324","DOIUrl":"10.1016/j.joei.2025.102324","url":null,"abstract":"<div><div>Alkaline oxidative fractionation of lignocellulosic biomass using O₂ to obtain lignin fraction and cellulose-rich substrate is one of the most promising strategies. This study systematically investigated the removal process and degradation products of carbohydrates and lignin at different stages through four intermittent alkaline oxidative treatments of sawdust, particularly revealing the molecular structural characteristics of extracted lignin through GPC, FTIR, and 2D-HSQC. After 4 treatments, 96.3 % of lignin, 93.5 % of xylose, 97.6 % of galactose, and 93.4 % of mannose were gradually extracted, resulting in a fiber solid containing 84.1 % glucose. The sawdust underwent four stages of structure looseness, crosslink weakening, structure disintegration, and fiber fragmentation during alkaline oxidative fractionation. The removal intensity of xylose, galactose, and mannose first increased and then decreased, reaching a peak of 53.7, 69.6, and 61.0 % respectively in the 2nd treatment. The glucose removal intensity followed a trend of first decreasing and then significantly increasing, having a low point of 7.2 % in the 3rd treatment. The 1st stage has the highest lignin removal and degradation rate, while the 3rd stage has the highest lignin removal intensity. The extracted lignin was oxidized and depolymerized into acid-insoluble lignin fragments (PL, 300-100,000 Da) and acid-soluble lignin fragments (ASL, 150–600 Da), where ASL contains more β-aryl ether and resinol linkages than PL. Part of the carbohydrates and lignin suffer severe oxidative degradation, generating large amounts of organic acids. These results contribute to the quantitative and qualitative understanding of lignin and carbohydrate extraction processes during alkaline oxidative treatment.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102324"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265043","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}

{"title":"Microwave vacuum catalytic co-pyrolysis of coconut shell and millet residues: parameters optimization and high-quality biofuel production","authors":"Ahmed Elsayed Mahmoud Fodah ,&nbsp;Taha Abdelfattah Mohammed Abdelwahab ,&nbsp;Nageh K. Allam ,&nbsp;Haoyu Xiao ,&nbsp;Ziyue Tang ,&nbsp;Xianhua Wang ,&nbsp;Haiping Yang","doi":"10.1016/j.joei.2025.102316","DOIUrl":"10.1016/j.joei.2025.102316","url":null,"abstract":"<div><div>Waste-to-energy offers a promising solution to address energy shortages while simultaneously reducing environmental pollution. The present study aimed to enhance the biofuel production by microwave vacuum co-pyrolysis of high-lignin biomass, i.e., coconut shells (CS), and high-hemicellulose biomass, i.e., millet residues (MR). Their complementary compositions enhance synergistic effects, improving product quality and process efficiency compared to individual pyrolysis. Also, bentonite was utilized as a low-cost catalyst, and the impact of vacuum and N₂ pyrolysis environments was compared. Firstly, multi-factor optimization, specifically co-feeding ratio, catalyst ratio, and pyrolysis environment, was performed to maximize bio-oil yield and its heating value using response surface methodology. Then, the intensive effect of the study variables on the quantity and quality of pyrolytic products has been investigated and assessed. The optimal pyrolysis condition was found to be a 1:3 C S:MR co-feeding ratio, 15 % catalyst ratio, and under vacuum pyrolysis environment. The results revealed that the bentonite catalyst promotes heating by increasing the heating rate and reaction temperature by 33 % and 26 % respectively, compared to the non-catalytic condition. Also, CS produces a high biochar yield, while MR results in high bio-oil and gas yields. Mixing CS/MR in a ratio of 1:3 and using bentonite enhanced the quality of the products under vacuum environment. Whereas higher hydrocarbon (27.5 %) bio-oil, low-ash (7 %) and high heating value (22.7 MJ/kg) biochar, and H₂-rich gas have been achieved. This promoted the net energy recovery, reaching a maximum value of 77 %.</div></div>","PeriodicalId":17287,"journal":{"name":"Journal of The Energy Institute","volume":"123 ","pages":"Article 102316"},"PeriodicalIF":6.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220080","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}