Journal of Supercritical Fluids最新文献

{"title":"Supercritical CO2-assisted preparation of catalytically-active Pd/Ni nanoparticle-embedded carbon from a metal-organic framework","authors":"Kiyoshi Matsuyama, Masashi Eiro, Ayano Shoji, Takafumi Kato","doi":"10.1016/j.supflu.2024.106500","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106500","url":null,"abstract":"A metal nanoparticle (NP)-carbon composite derived from metal-organic frameworks (MOFs) has garnered significant attention for its high catalytic activity. This study develops a simple method for preparing Pd/Ni NP-embedded carbon from MOFs. Palladium(Ⅱ) acetate (Pd(OAc)<ce:inf loc=\"post\">2</ce:inf>) is used as the precursor for Pd NPs and is loaded into the pores of Ni-MOF-74 using supercritical carbon dioxide (scCO₂) assisted immobilization. Pd/Ni NPs are prepared by reduction and pyrosis of Pd(OAc)<ce:inf loc=\"post\">2</ce:inf>-loaded Ni-MOF-74. Scanning transmission electron microscopy (STEM) clearly reveals that the Pd/Ni NPs are successfully immobilized in the carbon (Pd/Ni@C) and dispersed with sizes around 10 nm. Pd/Ni@C demonstrates high catalytic activity and high durability in Suzuki–Miyaura coupling reactions, despite having lower Pd content (4.7 wt%) than commercially available Pd@C (10 wt%). The active palladium species Pd(0) on Pd/Ni@C accelerated the Suzuki-Miyaura coupling reactions, because the Ni in Pd/Ni NPs played the sacrificial role to resist Pd-oxidation.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"279 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142874110","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":"Exploring the potential of deep eutectic systems for the preservation of the chemical profile and antibacterial potential of dill (Anethum graveolens L.) supercritical CO₂ extracts","authors":"Jelena Vladić, Igor Jerković, Valentina Pavić, Dragoljub Cvetković, Stela Jokić, Krunoslav Aladić, Kristian Pastor, Ana Rita C. Duarte","doi":"10.1016/j.supflu.2024.106499","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106499","url":null,"abstract":"This study evaluated the potential of deep eutectic systems (DESs) to enhance the chemical and microbiological stability, as well as the antibacterial activity of dill (<ce:italic>Anethum graveolens</ce:italic> L.) supercritical extracts, rich in carvone and limonene, over six months of storage. Various betaine-based DESs were tested for their ability to preserve the chemical integrity and enhance the antibacterial properties of dill extracts. Significant alterations in the headspace profile of extracts during storage indicated degradation reactions. The dill-Bet/LA extract system (dill extract in Bet/LA) proved most effective, significantly slowing degradation and enhancing antibacterial activity compared to the dill-control extract. Specifically, this system exhibited 20–40-fold greater efficacy against Gram-negative bacteria and 5–8-fold stronger activity against Gram-positive bacteria than the dill-control. Furthermore, the dill-Bet/LA system was also the most effective in preserving antimicrobial potency during storage, demonstrating its potential as a sustainable solution for extending the shelf life and bioactivity of dill supercritical extracts.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"28 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142874111","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":"Study of mechanism, kinetics, and product characterization of thermal and catalytic liquefaction of Northeastern Indian coals using supercritical toluene","authors":"Govind Dubey, Prabu Vairakannu, Pankaj Tiwari","doi":"10.1016/j.supflu.2024.106496","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106496","url":null,"abstract":"The present research aimed at the direct coal liquefaction (DCL) of three Indian coals with toluene and Fe<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf> catalyst within a temperature range of 400 ℃- 450 °C. The maximum overall conversion of 41.87 wt% and oil yield of 16.25 wt% was observed for lignite coal, at 60 min residence time and 450 ℃ for catalytic, with an increase of 6 % and 4.72 %, respectively, compared to that of thermal liquefaction. The activation energies were in the 40 kJ/mol to 370 kJ/mol range. The CO<ce:inf loc=\"post\">2</ce:inf> levels peaked at 15.45 vol% for catalytic and 11.18 vol% for thermal DCL in the case of lignite coal. The hydrogen sulfide and carbonyl sulfide gases with maximum concentrations of 563 ppm and 230 ppm, respectively, were also detected. The oil possesses carbon chains ranging from C<ce:inf loc=\"post\">8</ce:inf> to C<ce:inf loc=\"post\">25</ce:inf>, whereas both asphaltene and preasphaltene fractions extend to a broader range of C<ce:inf loc=\"post\">8</ce:inf>-C<ce:inf loc=\"post\">30</ce:inf>.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"48 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142874112","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 of solubility of terephthalic acid in water under hydrothermal conditions","authors":"Yu Su, Qingxin Zheng, Yoshiki Suga, Masaru Watanabe","doi":"10.1016/j.supflu.2024.106497","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106497","url":null,"abstract":"Here, the solubility of terephthalic acid (TPA) in water was measured under hydrothermal conditions at temperatures from 423.15 K to 623.15 K by a semi-dynamic gravimetric system. The whole process, using water as the only solvent, was considered safe and environmentally friendly. The results indicated that the TPA solubility in water increased exponentially with the temperature. Particularly, at 573.15 K (10 MPa) and 623.15 K (20 MPa), the water solubility of TPA was measured to be 108.1 and 347.4 g kg<ce:sup loc=\"post\">−1</ce:sup>, respectively. It was the first time to measure the TPA solubility in water at over 523.15 K experimentally. Fitted curves for the TPA solubility in water as functions of temperature and water density were plotted, and the thermodynamic properties for the dissolution of TPA into water were obtained and plotted. The TPA solubility results obtained would be helpful to improve the production or recycling of TPA under hydrothermal conditions.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"83 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142874116","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":"Comparative study of the corrosion behavior of Inconel 625 in supercritical water containing dissolved and molten phosphates","authors":"Jiquan Chen, Zitao Lin, Xingying Tang, Ke Li, Riguang Zhu, Jianqiao Yang","doi":"10.1016/j.supflu.2024.106495","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106495","url":null,"abstract":"This paper presents a comparative study of the corrosion behavior of Inconel 625 in supercritical water with different oxygen contents and phosphate phases. The results showed that the dissolved phosphate phase could compete with oxygen and that the addition of oxygen converted Cr<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf> to Cr<ce:sup loc=\"post\">6 +</ce:sup>, resulting in a reduction in the thickness of the oxide film. The oxide film formed consisted of three distinct layers. The outer layer consists of NiO, Fe<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf>, and NiFe<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">4</ce:inf>, which were formed by the diffusion of metal cations outward. The middle layer was a metal phosphate passivation layer which could prevent the diffusion of Fe, Ni, etc. and retard corrosion. The inner layer was formed by inward oxidation of oxygen ions with Cr to form Cr<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf>. Phosphate molten salt were highly corrosive and can directly dissolve Cr<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf> into soluble Cr<ce:sup loc=\"post\">3+</ce:sup>, a process accelerated by oxygen, increasing the Cr<ce:sup loc=\"post\">3+</ce:sup> content from 59.63 % to 77.54 %.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"64 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142874113","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":"Surrogate model based multi-objective optimisation of supercritical CO2 ejectors","authors":"Sanjoy Paul, R.P. Srikar, Srisha MV Rao, Pramod Kumar","doi":"10.1016/j.supflu.2024.106493","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106493","url":null,"abstract":"A supercritical CO<ce:inf loc=\"post\">2</ce:inf> (sCO<ce:inf loc=\"post\">2</ce:inf>) supersonic ejector improves the coefficient of performance (COP) in combined power and cooling systems by compressing a secondary stream through entrainment and mixing with a high-momentum primary stream. The performance of the ejector is crucial to system efficiency and is influenced by complex gas dynamic shock interactions and shear layers which is further complicated by the rapid variations in thermophysical of sCO<ce:inf loc=\"post\">2</ce:inf>. In this regard, aerodynamic duct shaping plays a pivotal role in optimizing ejector efficiency. The present paper seeks to optimize a sCO<ce:inf loc=\"post\">2</ce:inf> ejector using a surrogate model derived from computational fluid dynamics data. The model relies on a comprehensive dataset generated using a simulation tool coupled with REFPROP database to account for variations in thermophysical properties of sCO<ce:inf loc=\"post\">2</ce:inf>. Subsequently, a genetic aggregation technique is used to train and improve the model via supervised machine learning. The influence of critical design parameters such as radius of mixing section, nozzle exit point, and mixing duct length on the performance of the ejector is enabled by a sensitivity analysis study facilitated by design space exploration. Finally, a multi-objective evolutionary algorithm is incorporated in the surrogate model to optimize the ejector performance by maximizing entrainment ratio and compression ratio, while minimizing entropy generation. It is found that stagnation temperature ratio is a key influencing parameter responsible for enhancing mixing layer growth to improve the ejector performance. The optimized ejector shows an enhanced efficiency of ∼ 25 % compared to a non-optimized ejector.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"31 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142874114","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":"Dual split transcritical carbon dioxide cycle based on all engine operating conditions with high thermal adaptability","authors":"Hua Tian, Cheng Chang, Ligeng Li, Xianyu Zeng, Jianfeng Wang, Minghuan Yin, Yongchuan Wang, Jian Gong, Xuanang Zhang, Gequn Shu","doi":"10.1016/j.supflu.2024.106490","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106490","url":null,"abstract":"To achieve carbon peaking and carbon neutrality goals, the CO2 transcritical power cycle is regarded as a promising technology for waste heat recovery. Variations in the working conditions of the engine can lead to significant fluctuations in waste heat. Therefore, to enhance adaptability to changes in heat sources, this study focuses on natural gas engines and proposes a dual split flow system for the CO2 transcritical power cycle based on heat capacity matching. This system features two diversion designs that can actively adjust the mass flow rate of carbon dioxide through different heat sources, thereby actively adjusting the equivalent heat capacity of the working fluid and matching the changes in heat sources under varying operating conditions. Based on actual road conditions, this study establishes a dynamic model of system and proposes a flow adaptive allocation control strategy for achieving heat capacity matching. The study conducted simulations of the dynamic system of the waste heat recovery system under all engine operating conditions, and interesting results showed that CO2 transcritical power cycle achieved positive net power output under all engine operating conditions, with over 91 % of engine operating conditions achieving a cylinder liner water utilization rate greater than 99 %, under the studied engine operating conditions, the flue gas utilization rate was greater than 92.2 %, and the engine BTE increased by 2.96 −7.04 %.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"47 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825385","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":"Multiphase equilibria modeling with GCA-EOS. Part III: CO2 with the homologous series of carboxylic acids","authors":"Jacqueline Mansano Ortega, Vladimir Ferreira Cabral, Francisco Adrián Sánchez","doi":"10.1016/j.supflu.2024.106489","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106489","url":null,"abstract":"Knowledge of phase equilibria and critical properties of CO<ce:inf loc=\"post\">2</ce:inf> + carboxylic acid systems is essential for supercritical fluid extraction (SCFE) processes, such as oil deacidification. However, modeling these systems is challenging due to their highly asymmetrical behavior. In this study, we apply the Group Contribution with Association Equation of State (GCA-EOS) to model vapor−liquid and liquid−liquid equilibria of the homologous series of CO<ce:inf loc=\"post\">2</ce:inf> + carboxylic acids. The GCA-EOS, previously validated for alkanes and alcohols, is extended to cover short and long-chain carboxylic acids. Using a single set of parameters, we validate the model against experimental data for C<ce:inf loc=\"post\">2</ce:inf>−C<ce:inf loc=\"post\">20</ce:inf> acids, temperatures from 293 K to 473 K, and pressures up to 400 bar. The model successfully predicts phase equilibria across the entire homologous series, making it a reliable tool for assessing the multiphase behavior of these systems in SCFE applications.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"23 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825386","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":"Complex phase behaviours related to gas injection in reservoir fluids","authors":"F.E. Benelli, G.O. Pisoni, M. Cismondi-Duarte","doi":"10.1016/j.supflu.2024.106475","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106475","url":null,"abstract":"Enhanced oil recovery (EOR) involves several techniques, including the injection of gas (such as natural gas, nitrogen, or <mml:math altimg=\"si86.svg\" display=\"inline\"><mml:msub><mml:mrow><mml:mi mathvariant=\"normal\">CO</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>) into the reservoir to increase its pressure, thereby displacing oil from one or more injection wells to production wells. For this process to be effective, it is essential that the injected gas and the oil reach a homogeneous state. Particularly, the First-Contact Minimum Miscibility Pressure (FC-MMP) offers a reliable (and safe) initial estimate for the pressure at which the EOR process should be conducted. In this work, an efficient algorithm is developed that allows computing complete pressure(P)-<mml:math altimg=\"si2.svg\" display=\"inline\"><mml:mi>α</mml:mi></mml:math> diagrams (<mml:math altimg=\"si2.svg\" display=\"inline\"><mml:mi>α</mml:mi></mml:math>: percentage of injected gas) at a fixed temperature using traditional cubic equations of state (EoS), including complex cases with three-phase regions. This algorithm is used to study both the qualitative and quantitative behaviour of the P-<mml:math altimg=\"si2.svg\" display=\"inline\"><mml:mi>α</mml:mi></mml:math> diagrams and to analyse how FC-MMP changes with the injection of different gases or gas mixtures. Various reservoir fluids from the literature (with and without asphaltenes and with varying levels of <mml:math altimg=\"si86.svg\" display=\"inline\"><mml:msub><mml:mrow><mml:mi mathvariant=\"normal\">CO</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math> and methane) are evaluated. In one section, three injection gases are used: <mml:math altimg=\"si86.svg\" display=\"inline\"><mml:msub><mml:mrow><mml:mi mathvariant=\"normal\">CO</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>, <mml:math altimg=\"si75.svg\" display=\"inline\"><mml:msub><mml:mrow><mml:mi mathvariant=\"normal\">N</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>, and a synthetic natural gas mixture, comparing their effects on the P-<mml:math altimg=\"si2.svg\" display=\"inline\"><mml:mi>α</mml:mi></mml:math> diagrams. Then, the impact of interaction parameters on phase equilibrium and FC-MMP is analysed, and the role of asphaltene precipitation is discussed. The study concludes with a quantitative comparison between the FC-MMP calculated here and the Multiple-Contact MMP (MC-MMP) reported for the same fluids. Additionally, the problem of whether asphaltenes precipitation should be considered or ignored in the determination of the FC-MMP is analysed and discussed, with different perspectives for conventional and non-conventional shale type reservoirs.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"18 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789991","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":"High concentrations of CO and CO2 inhibit lignite gasification in supercritical water","authors":"Rui Zhang, Shuaiqi Zhao, Han Huang, Kunpeng Zhao, Bofeng Bai","doi":"10.1016/j.supflu.2024.106486","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106486","url":null,"abstract":"Supercritical water gasification (SCWG) technology enables the efficient utilisation of lignite to produce H<ce:inf loc=\"post\">2</ce:inf>, CO, and CO<ce:inf loc=\"post\">2</ce:inf>. Coal gasification differs under different atmospheres and H<ce:inf loc=\"post\">2</ce:inf> promotes the pyrolysis of carbon structures. While simultaneous increases in H<ce:inf loc=\"post\">2</ce:inf>, CO, and CO<ce:inf loc=\"post\">2</ce:inf> are observed, their combined effect on the SCWG of coal remains unknown. Formic acid (FA) was used to produce H<ce:inf loc=\"post\">2</ce:inf>, CO, and CO<ce:inf loc=\"post\">2</ce:inf> in the supercritical water, and the impact of the gaseous product generated from high-concentration (&gt;30 wt%) FA decomposition on the SCWG of lignite was experimentally investigated. In comparison to lignite gasification in pure supercritical water, the carbon efficiency of lignite gasification in 30 wt% FA solution decreased by 7.66 %, and the mass conversion of lignite decreased by 4.0 %. Higher concentrations of CO and CO<ce:inf loc=\"post\">2</ce:inf> yielded stronger inhibition of lignite SCWG.","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"20 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789992","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}