Journal of Supercritical Fluids最新文献

{"title":"Performance of convective heat transfer of supercritical CO2 in unilaterally heated rectangular channel","authors":"Shang Mao ,&nbsp;Shengli Zhang ,&nbsp;Xuehong Wu ,&nbsp;Yong Liu ,&nbsp;Leigang Zhang ,&nbsp;Cai Lv ,&nbsp;Tao Zhou ,&nbsp;Songzhen Tang","doi":"10.1016/j.supflu.2026.106895","DOIUrl":"10.1016/j.supflu.2026.106895","url":null,"abstract":"<div><div>The utilization of supercritical CO₂ (sCO₂) for cooling aero-engine combustion chambers can effectively alleviate the hydrocarbon fuel slagging issue in hypersonic vehicles. Nevertheless, research on sCO₂ heat transfer and performance optimization in regenerative cooling channels under high heat flux unilateral heating conditions remains limited. Influence of heat flux, mass flux, operating pressure and heating position on the flow dynamics and heat transfer was numerically investigated. Results indicated that wall temperature (<em>T</em>_w) peak intensified with increase of heat flux and decrease of pressure and mass flux. Heat transfer deterioration (HTD) can be alleviated by elevating inlet temperature above the pseudo-critical temperature <em>T</em>_in&gt;<em>T</em>_pc. Furthermore, temperature non-uniformity coefficient served as an effective predictor of heat sink performance of regenerative cooling channels. A lower coefficient indicated a higher heat sink utilization rate. Analysis revealed that turbulent kinetic energy within the boundary layer was primary factor governing heat transfer performance. Friction loss dominated and acceleration loss comprised approximately 1/4 of total pressure drop. Comparative assessment demonstrated that top heating led to the highest <em>T</em>_w, whereas side heating induced the greatest pressure drop. Finally, sinusoidal wavy channels were proposed, with amplitude <em>A</em>= 0.2 mm and period <em>p</em> = 4 mm exhibiting optimal flow and heat transfer capabilities for various heating position.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"232 ","pages":"Article 106895"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145981962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two-stage flow reactions of α-pinene to p-cymene by combining subcritical and supercritical water","authors":"Yumi Okita,&nbsp;Yoshito Oshima,&nbsp;Makoto Akizuki","doi":"10.1016/j.supflu.2026.106920","DOIUrl":"10.1016/j.supflu.2026.106920","url":null,"abstract":"<div><div>Subcritical and supercritical water have attracted attention as tunable reaction media for organic reactions because their properties can be adjusted by controlling temperature and pressure. It is expected that the appropriate solvent properties will be used for each step of a multi-step reaction process by changing only the temperature and pressure. In this study, <em>α</em>-pinene was converted to <em>p</em>-cymene using a two-stage flow reactor where subcritical and supercritical water were used as solvents. The synthesis involved acid-catalyzed isomerization and oxidative dehydrogenation. For determining appropriate reaction conditions for acid-catalyzed isomerization with WO_X/TiO₂ as a solid catalyst (first stage) and oxidative dehydrogenation (second stage), the temperature, pressure, initial concentration of oxidant (second stage), and starting compound (second stage) for each stage were investigated. The results confirm that the maximum yield of <em>p</em>-cymene exceeded 0.4 when the first stage temperature was set to 250 °C or 300 °C; the second stage temperature was set to 400 °C, and the pressure for both stages was set to 30 MPa. This yield value was approximately twice as large compared to the yield values of <em>p</em>-cymene synthesized in a single-stage flow reactor in supercritical water at 400 °C and 30 MPa. The first stage involved ion-mediated reactions, while the second stage involved radical-mediated reactions. Since the reactivity of these reactions differs between subcritical and supercritical water, and the reactivity can be adjusted by pressure, combining subcritical and supercritical conditions in two-stage reactors increased the target product yield.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"232 ","pages":"Article 106920"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146109699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement and prediction of levofloxacin and metacetamol solubility in supercritical carbon dioxide","authors":"Yung-Chun Yang ,&nbsp;Hsu-Chen Wang ,&nbsp;Chie-Shaan Su ,&nbsp;Chieh-Ming Hsieh","doi":"10.1016/j.supflu.2026.106915","DOIUrl":"10.1016/j.supflu.2026.106915","url":null,"abstract":"<div><div>The solubility of pharmaceutical compounds in supercritical carbon dioxide (scCO₂) is crucial for process development. In this study, the solubility of levofloxacin and metacetamol was measured using a high-pressure semi-flow apparatus at 313.2 K, 323.2 K, and 333.2 K, over a pressure range of 12 MPa to 24 MPa for levofloxacin and 12 MPa to 22 MPa for metacetamol. Solubilities (in mole fraction) ranged from 1.51 × 10⁻⁷ to 2.71 × 10⁻⁶ for levofloxacin and from 8.00 × 10⁻⁷ to 7.32 × 10⁻⁶ for metacetamol. Semi-empirical correlations proposed by Chrastil, Mendez-Santiago &amp; Teja, Kumar &amp; Johnston, and Bartle reproduced the data with average absolute relative deviations (AARD-<em>y</em>) of 2.89–3.90 % for levofloxacin and 2.64–6.73 % for metacetamol. Two thermodynamic models based on the Peng-Robinson equation of state (PR EOS), PR+VDW and PR+MHV1 +Wilson, were also used to correlate the data, giving AARD values of 8.53 % and 23.6 % for levofloxacin, and 4.53 % and 8.21 % for metacetamol, respectively. In addition, the PR EOS was combined with COSMO-SAC through the MHV1 mixing rule to enable solubility prediction without adjusting system-specific parameters. This predictive framework yielded average logarithmic deviation (ALD-<em>y</em>) values of 0.229 for levofloxacin and 0.169 for metacetamol, corresponding to AARDs of 39.5 % and 48.7 %.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"232 ","pages":"Article 106915"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146033094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction and optimization of a low-pressure direct-fired semi-closed CO2 cycle based on the temperature rise patterns of working fluid compression","authors":"Enhui Sun ,&nbsp;Weiqi Zhang ,&nbsp;Zhenyu Leng ,&nbsp;Qinchai Chen ,&nbsp;Jinliang Xu ,&nbsp;Tai Wang ,&nbsp;Zhiming Qin","doi":"10.1016/j.supflu.2026.106902","DOIUrl":"10.1016/j.supflu.2026.106902","url":null,"abstract":"<div><div>Oxygen-enriched direct-combustion cycles hold significant potential for efficient carbon capture. However, mainstream technologies face inherent limitations regarding operating pressure and system complexity. The excessive temperature rise during working fluid compression remains a primary bottleneck in constructing these systems. Based on a thermodynamic analysis of gas compression processes, this study reveals an intrinsic correlation between compression temperature rise and the molecular degrees of freedom. Specifically, it is found that the compression temperature rise of triatomic gases (e.g., CO₂) is significantly lower than that of diatomic gas mixtures (such as air). Building on this theoretical insight, the feasibility of constructing a low-pressure, subcritical CO₂ direct-recuperative Brayton cycle (LPBC) is demonstrated. This approach breaks the conventional parameter selection paradigm for semi-closed Brayton cycles, greatly reducing the difficulty and complexity of system construction. To further unlock the potential of this cycle, direct-contact spray cooling is introduced to replace conventional intercooling. Numerical simulations demonstrate that this method achieves near-isothermal compression with a minimal pressure drop of only 20 Pa. Consequently, the optimized system (III-LPBC) achieves a thermal efficiency of 66.09 %, surpassing that of typical high-pressure cycles (63.43 %). This study not only provides a theoretical framework for working fluid selection based on molecular properties but also offers a novel technical pathway for constructing next-generation fossil fuel-based power generation systems that balance high efficiency, operational flexibility, and low-carbon emissions.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"232 ","pages":"Article 106902"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146000779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance evaluation and optimization of a coupled system integrating compressed carbon dioxide energy storage with double reheat thermal power unit","authors":"Guang Yan,&nbsp;Du Wang,&nbsp;Mujie Xue,&nbsp;Jian Lu,&nbsp;Rongyao Jia","doi":"10.1016/j.supflu.2026.106890","DOIUrl":"10.1016/j.supflu.2026.106890","url":null,"abstract":"<div><div>To enhance the peak load regulation capacity of thermal power units and improve the flexibility of power systems, this paper investigates the integration of a compressed carbon dioxide energy storage system with a 1000 MW double reheat thermal power unit. A thermodynamic model is developed for the power plant as well as for supercritical, transcritical, and liquid compressed carbon dioxide energy storage systems, and the effects of various coupling methods on the plant's performance are analyzed. Three types of compressed carbon dioxide energy storage systems and a double reheat thermal power plant coupling system are selected with the aim of minimizing heat consumption. The paper thoroughly examines the influence of key parameters on the thermal efficiency of the system and employs genetic algorithms for optimization. The results indicate that liquid compressed carbon dioxide energy storage is more suitable for coupling with double reheat thermal power units compared to supercritical or transcritical carbon dioxideenergy storage systems. The coupling process is as follows: during the energy storage phase, steam from the medium-pressure cylinder’s final stage is extracted to drive a small steam turbine for compression work, with the generated heat being absorbed by the power unit’s condensation water and returned to the low-pressure inlet of No.7. During the energy release phase, steam from the low-pressure cylinder’s first stage is extracted to heat the CO₂ entering the turbine, which is then returned to the low-pressure heater drain outlet of No.7. Among the key parameters, the inlet temperature of the second-stage compressor, the system expansion ratio, and the inlet temperatures of the first- and second-stage turbines have the greatest impact on system performance. Under the design conditions, the energy storage efficiency of the liquid carbon dioxide system is 56.97 %, the overall system efficiency is 46.27 %, the levelized cost of electricity is 0.118528 $/kWh, the energy storage density reaches 14.343 kWh/m³ , and the coal consumption rate is 256.61 g/kWh. After optimization, the coupled system efficiency can be improved by 1.23 %, and the LCOE can be reduced by 7.64 %. The coupling of liquid carbon dioxide energy storage with double reheat thermal power units can significantly enhance system flexibility and peak load regulation capabilities. This study offers valuable insights for engineering applications.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"232 ","pages":"Article 106890"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase equilibria of solution mixture for allyl phenylacetate, amyl phenylacetate and benzyl phenylacetate systems under supercritical CO2","authors":"Uma Sankar Behera ,&nbsp;Hakyeong Kim ,&nbsp;Hun-Soo Byun","doi":"10.1016/j.supflu.2026.106924","DOIUrl":"10.1016/j.supflu.2026.106924","url":null,"abstract":"<div><div>The growing industrial relevance of phenylacetate derivatives, driven by their unique properties and wide-ranging applications, underscores the importance of accurate vapor–liquid equilibrium (VLE) data, particularly for separation processes using supercritical CO₂ as a sustainable solvent. This study investigates the phase behavior of binary systems composed of CO₂ with allyl, amyl, and benzyl phenylacetates over a temperature range of 313.2–393.2 K and pressures up to 24.97 MPa. Literature studies and thermodynamic databases such as DETHERM and DECHEMA indicate that phase equilibrium data for these systems under supercritical conditions have not been reported previously. The pressure–temperature profiles revealed that the critical mixture curves connect the critical points of the pure components, exhibiting Type-I behavior as described by van Konynenburg and Scott. In all three systems, increasing the phenylacetate concentration enhanced solubility and reduced system pressure at constant temperature. The experimental bubble point data were fitted using the Peng–Robinson equation of state (PR EoS) combined with the van der Waals one-fluid mixing rule. The binary interaction parameters were optimized for each system: allyl phenylacetate (k_ij = 0.040, η_ij = –0.040), amyl phenylacetate (k_ij = 0.055, η_ij = –0.045), and benzyl phenylacetate (k_ij = 0.040, η_ij = –0.050). The model demonstrated good agreement with the experimental measurements, yielding root mean square deviation (RMSD) values between 5.64 % and 8.86 % across all investigated systems and operating conditions.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"232 ","pages":"Article 106924"},"PeriodicalIF":4.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146134624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Valorization of Eucalyptus grandis × Eucalyptus urophylla leaves using supercritical fluid extraction: Yield optimization, chemical composition, and bioactivities","authors":"See Cheng Yip ,&nbsp;Lai Yee Ho ,&nbsp;Yee Ho Chai ,&nbsp;Nam Weng Sit","doi":"10.1016/j.supflu.2026.106892","DOIUrl":"10.1016/j.supflu.2026.106892","url":null,"abstract":"<div><div><em>Eucalyptus grandis</em> × <em>Eucalyptus urophylla</em> has been cultivated on a large scale in Malaysia for its timber values. Its leftover leaves are considered agricultural waste. This study aimed to optimize extraction yields and evaluate the chemical composition and bioactivities of leaf extracts from <em>Eucalyptus</em> hybrid produced using supercritical fluid extraction (SFE) with carbon dioxide. Leaves were collected from <em>Eucalyptus</em> hybrid trees aged 17 months to 31 months (group A) and 40 months to 50 months (group B). Optimization using response surface methodology (RSM) identified optimal extraction conditions (pressure, temperature, and time) as 29.7 MPa, 79.8 °C, and 116.2 min for A, and 30.0 MPa, 79.6 °C, and 108.6 min for B. Gas chromatography-mass spectrometry (GC-MS) showed that eucalyptol (18.82 %) and eucalyptin (16.46 %) were the dominant compounds in A and B, respectively. Incorporation of 10 % ethanol as co-solvent increased the SFE yield by approximately 10-fold from 0.475 % (w/w) (A) to 4.650 % (w/w) (A10) and 0.255 % (w/w) (B) to 2.640 % (w/w) (B10). All extracts demonstrated antimicrobial activity, with minimum inhibitory concentrations ranging from 0.02 mg/mL to 2.50 mg/mL against 10 bacterial strains, and 0.02 mg/mL to 1.25 mg/mL against seven fungal strains. The extracts were generally more effective against Gram-positive bacteria and exhibited variable antifungal activity depending on the fungal species. Notably, the ethanol-assisted SFE extract from B showed the strongest larvicidal activity against <em>Aedes aegypti</em> (LC₅₀: 187.02 µg/mL) and <em>Aedes albopictus</em> (LC₅₀: 294.48 µg/mL) after 48-hour exposure. These findings suggest that <em>Eucalyptus</em> hybrid leaves are a promising source of bioactive compounds with potential applications as disinfectants and mosquito larvicides.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"231 ","pages":"Article 106892"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 study on supercritical CO₂ flow and heat transfer in rectangular microchannel PCHE under recompression cycle conditions","authors":"Shishen Cheng ,&nbsp;Yan Ren ,&nbsp;Ruowen Jiang ,&nbsp;Mengjie Song ,&nbsp;Weidong Wu ,&nbsp;Yingying Yang ,&nbsp;Qiguo Yang","doi":"10.1016/j.supflu.2025.106873","DOIUrl":"10.1016/j.supflu.2025.106873","url":null,"abstract":"<div><div>Rectangular microchannel printed circuit heat exchangers (RM-PCHEs) exhibit excellent flow and heat transfer characteristics. However, within the operating range of low-temperature recuperator for the supercritical carbon dioxide (SCO₂) Brayton recompression cycle, their performance data remain scant for hot-side inlet temperatures ranging from 373.8 K to 423.4 K. To address this gap, this study conducted experimental research on the flow and heat transfer characteristics of an RM-PCHE using SCO₂ as the working fluid, based on a comprehensive performance test system for heat exchangers. The results showed that the heat transfer performance of test sample was most significantly influenced by SCO₂ inlet temperature, with a 4.3 % increase in <em>Q</em>_ave and a 1.3 % decrease in <em>UA</em> for every 1 % increase in <em>T</em>_hot,i, and a 3.6 % increase in <em>ε</em> for every 1 % increase in <em>T</em>_cold,i. Besides, the test sample was most greatly influenced by mass flow rate, with a 1.5 % decrease in Δ<em>P</em>_hot for every 1 % decrease in <em>m</em>_hot, and a 1.7 % in Δ<em>P</em>_cold for every 1 % decrease in <em>m</em>_cold. Finally, test sample demonstrated enhanced thermal hydraulic performance, achieving maximum <em>UA</em> and <em>ε</em> values of 414.8 W·K⁻¹ and 0.92, respectively, while the maximum pressure drops on hot- and cold-side were 42.0 kPa and 13.9 kPa, respectively.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"231 ","pages":"Article 106873"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Semi-continuous subcritical hydrothermal conversion of lignin-rich defatted olive pomace","authors":"Alex Schulz ,&nbsp;William Santos Fagundes ,&nbsp;Leonardo Ramos Ten Caten ,&nbsp;Francisco Dalcin Vezaro ,&nbsp;Crisleine Perinazzo Draszewski ,&nbsp;Leoni Nogueira Brondani ,&nbsp;Michel Brondani ,&nbsp;João Henrique Cabral Wancura ,&nbsp;Flávio Dias Mayer ,&nbsp;Ederson Rossi Abaide","doi":"10.1016/j.supflu.2025.106874","DOIUrl":"10.1016/j.supflu.2025.106874","url":null,"abstract":"<div><div>Defatted olive pomace (DOP) is an abundant and low-cost agro-industrial residue that can be repurposed as an alternative to conventional uses such as direct combustion, animal feed, and land disposal. DOP has potential for the production of value-added products including biocrude (BC), hydrochar (HC), fermentable sugars (FS), and platform chemicals (PC) through the depolymerization of holocellulose and lignin present in its composition. The objective of this study was to evaluate the influence of temperature (250 and 300 ºC) and water-to-biomass ratio (15, 20, and 25) on the yields of BC, HC, FS, and PC through semi-continuous subcritical hydrothermal liquefaction of DOP. The highest yields were achieved at 300 °C with a water-to-DOP ratio of 25, resulting in values of 38.50 ± 3.13, 5.78 ± 1.07, 6.74 ± 1.67, and 2.84 ± 0.13 g/100 g for BC, HC, FS, and PC, respectively. The higher heating values (HHV) of BC and HC were 29.11 ± 0.05 and 26.01 ± 1.18 MJ/kg, respectively—comparable to values reported in other studies with both similar and different residues.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"231 ","pages":"Article 106874"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating thermodynamic and kinetic behaviors of industrial contaminated lean monoethylene glycol in methane gas hydrate inhibition","authors":"Mahmood Riyadh Atta ,&nbsp;Bhajan Lal ,&nbsp;Khor Siak Foo","doi":"10.1016/j.supflu.2026.106891","DOIUrl":"10.1016/j.supflu.2026.106891","url":null,"abstract":"<div><div>Regenerated lean monoethylene glycol (LMEG) is widely reused as a thermodynamic hydrate inhibitor in offshore gas production; however, contaminant accumulation during regeneration cycles alters its inhibition performance. This study presents a combined thermodynamic and kinetic evaluation of industrially regenerated LMEG in a methane hydrate system. Hydrate–liquid–vapor equilibrium (HLVE), suppression temperature, induction time, gas uptake, and hydrate conversion were experimentally quantified using a high-pressure sapphire cell for (5−15) wt% LMEG solutions. Thermodynamic measurements show that regenerated LMEG produces average suppression temperatures of approximately (1.4, 2.6, and 4.2) °C for (5, 10, and 15) wt%, respectively, accompanied by a systematic rightward shift of HLVE curves relative to fresh MEG models. Kinetic analysis reveals that induction time increases from 33.8 min (5 wt%) to 58.0 min (15 wt%) at 80 bar, indicating a concentration-dependent delay in hydrate nucleation. Despite delayed nucleation, higher LMEG concentrations sustain elevated post-induction gas uptake, with methane gas-to-hydrate conversion exceeding 95 % at 15 wt% after 300 min. These results demonstrate a contamination-driven dual inhibition behavior in which reduced thermodynamic efficiency is partially offset by enhanced kinetic retardation. The findings highlight the need for combined thermodynamic–kinetic performance metrics when assessing regenerated MEG for industrial hydrate management.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"231 ","pages":"Article 106891"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}