Journal of Supercritical Fluids最新文献_第10页

Effect of stirring and KOH/NaOH ratio on phase formation in hydrothermal synthesis of KNbO3-NaNbO3 particles 水热合成 KNbO3-NaNbO3 粒子过程中搅拌和 KOH/NaOH 比率对相形成的影响

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-30 DOI: 10.1016/j.supflu.2024.106340

Ellawala K. Chandima Pradeep, Alexandre Chauvel, Cenk Abdurrahmanoglu, Ragnar Kiebach, Astri Bjørnetun Haugen

{"title":"Effect of stirring and KOH/NaOH ratio on phase formation in hydrothermal synthesis of KNbO3-NaNbO3 particles","authors":"Ellawala K. Chandima Pradeep, Alexandre Chauvel, Cenk Abdurrahmanoglu, Ragnar Kiebach, Astri Bjørnetun Haugen","doi":"10.1016/j.supflu.2024.106340","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106340","url":null,"abstract":"<div>This study investigates the hydrothermal synthesis of KNbO3-NaNbO3 particles, which contains compositions of interest as lead-free piezoelectric materials. Precursor solutions containing Nb2O5, NaOH/KOH were hydrothermally reacted at 190 0C for 15 hours using either a conventional reactor or a reactor with stirring. For 50 % KOH or lower, the product was cubic or elongated cuboid/belt-shaped NaNbO3, whereas solely KOH resulted in hexagonal plate-like KNbO3. When 75 % KOH was used, the product was a mixture of large K5Na3Nb6O19·9 H2O hexagonal plates and smaller NaNbO3 cubes. We hypothesized this phase segregation was induced by highly concentrated microenvironments, and stirring would prevent that. Accordingly, stirring hydrothermal treatment of 75 % KOH solution produced only K5Na3Nb6O19·H2O hexagonal plates, which could be transformed to K0.7Na0.3NbO3 by calcination. By reducing the hydrothermal treatment time to 1 – 6 hours we isolated reaction intermediates, and based on them propose a kinetics-controlled mechanism for hydrothermal reactions of Nb2O5 and KOH/NaOH.</div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"212 ","pages":"Article 106340"},"PeriodicalIF":3.4,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S089684462400175X/pdfft?md5=9896c0d608550f2b36abe1d0085df976&pid=1-s2.0-S089684462400175X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141607432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Amphoteric SnO2 nanoparticles via pH-controlled continuous flow solvothermal synthesis 通过 pH 值控制的连续流溶热合成技术制备两性氧化锡纳米粒子

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-26 DOI: 10.1016/j.supflu.2024.106341

Aref Mamakhel , Magnus Kløve , Martin Bondesgaard , Troels L. Christiansen , Steen Uttrup Pedersen , Jørgen Skibsted , Bo Brummerstedt Iversen

{"title":"Amphoteric SnO2 nanoparticles via pH-controlled continuous flow solvothermal synthesis","authors":"Aref Mamakhel , Magnus Kløve , Martin Bondesgaard , Troels L. Christiansen , Steen Uttrup Pedersen , Jørgen Skibsted , Bo Brummerstedt Iversen","doi":"10.1016/j.supflu.2024.106341","DOIUrl":"10.1016/j.supflu.2024.106341","url":null,"abstract":"<div>Amphoteric oxides can be challenging to produce in phase pure form due to their sensitivity to the pH of the reaction mixture. The high-pressure, high-temperature reaction conditions of hydrothermal processes make the pH difficult to control. Here we report a simple approach to obtain nanoparticles of amphoteric oxides, where cheap metal nitrate precursors are reacted in alcohol (2-propanol) water mixtures (25 vol%:75 vol%) to maintain a neutral pH under solvothermal conditions. Phase pure SnO2 nanoparticles were synthesized in a continuous flow solvothermal reactor at 250 °C, 300 °C, 350 °C and 400 °C with sizes ranging from 3 nm to 7 nm. The nanoparticles were characterized using powder X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy, Raman spectroscopy, 119Sn MAS NMR spectroscopy, Brunauer-Emmett-Teller nitrogen adsorption, UV–VIS, and as anode material in CR2032 Li-ion battery cells. To demonstrate generality, amphoteric oxides ZnO, Bi2O3, Cr2O3 and γ-AlOOH were also synthesized.</div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"212 ","pages":"Article 106341"},"PeriodicalIF":3.4,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0896844624001761/pdfft?md5=fa89cf655ae986f2f7fd6596993da994&pid=1-s2.0-S0896844624001761-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141556763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Measurement and modeling of the electrical conductivity of organic electrolyte solutions and their mixtures with compressed CO2 有机电解质溶液及其与压缩二氧化碳混合物电导率的测量与建模

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-26 DOI: 10.1016/j.supflu.2024.106338

Marvin Dorn , Lukas Franke , Paul Figiel , Sabine Kareth , Eckhard Weidner , Christoph Held , Marcus Petermann

{"title":"Measurement and modeling of the electrical conductivity of organic electrolyte solutions and their mixtures with compressed CO2","authors":"Marvin Dorn , Lukas Franke , Paul Figiel , Sabine Kareth , Eckhard Weidner , Christoph Held , Marcus Petermann","doi":"10.1016/j.supflu.2024.106338","DOIUrl":"10.1016/j.supflu.2024.106338","url":null,"abstract":"<div>The electrochemical carbon dioxide reduction reaction (CO2RR) is of increasing importance for the development of a closed carbon cycle. Here, electrolytes are often used to increase the electrical conductivity and thus the current density. In addition, the use of compressed CO2 and electrolyte-containing organic solvents suppresses hydrogen evolution. However, the electrical conductivity of CO2-saturated electrolyte solutions is mostly unknown. Therefore, their electrical conductivity was investigated in this work at different electrolyte concentrations, pressures (up to 150 bar) and temperatures (298.15 K and 343.15 K). In addition, the simplified Mean Spherical Approximation (MSA-simple) model, supported by ePC-SAFT for density modeling, was used to successfully model the conductivity. The results show that CO2-saturated electrolyte solutions generally exhibit lower conductivities than CO2-free electrolyte solutions. However, at very low electrolyte and CO2 concentrations, the conductivities were higher in CO2-saturated electrolyte solutions than in CO2-free electrolyte solutions, which is a new finding in the literature.</div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"212 ","pages":"Article 106338"},"PeriodicalIF":3.4,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0896844624001736/pdfft?md5=95fd1acbf1ab9cbd8710a02275c15cc1&pid=1-s2.0-S0896844624001736-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141464132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Effect of supercritical carbon dioxide on pore structure and methane adsorption of shale with different particle sizes 超临界二氧化碳对不同粒径页岩的孔隙结构和甲烷吸附的影响

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-26 DOI: 10.1016/j.supflu.2024.106343

Liang Wang , Yuechen Zhao , Minxuan Liu , Zihang Song , Yiwei Sun , Sijia Ni , Shenguang Fu , Rongkun Pan

{"title":"Effect of supercritical carbon dioxide on pore structure and methane adsorption of shale with different particle sizes","authors":"Liang Wang , Yuechen Zhao , Minxuan Liu , Zihang Song , Yiwei Sun , Sijia Ni , Shenguang Fu , Rongkun Pan","doi":"10.1016/j.supflu.2024.106343","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106343","url":null,"abstract":"<div>Supercritical carbon dioxide (SCCO2) fracturing significantly enhances shale gas recovery, which is influenced by particle size. We soaked shale in SCCO2 and investigated the impact of SCCO2 on different particle sizes. Large-particle shales showed the largest percentage changes in specific surface area and total pore volume (54.11 %, 87.87 %; 58.59 %, 76.32 %) followed by small-particle size shales. This trend was also observed in other pore structure parameters. The particle-size effect is: Large-particle shale, with abundant microfractures, enhances SCCO2 flow and pore alteration. Small-particle shale's high specific surface area facilitates SCCO2 penetration. Medium-particle shale is less affected due to balanced interactions of these factors. Methane is primarily found in large and medium pores and microfractures. Methane adsorption in shale mainly involves multi-layer adsorption. Following SCCO2 treatment, pore fractures narrowed, increasing the proportion of methane molecules adsorbed as a single-layer. This study is crucial for evaluating the fracturing effects on shale gas wells.</div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"212 ","pages":"Article 106343"},"PeriodicalIF":3.4,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141542931","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}

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Liposomes and niosomes production by a supercritical CO2 assisted process for topical applications: A comparative study 通过超临界二氧化碳辅助工艺生产局部应用的脂质体和niosomes：比较研究

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Journal of Supercritical Fluids Pub Date : 2024-06-26 DOI: 10.1016/j.supflu.2024.106342

Lucia Baldino, Domenico Riccardi, Ernesto Reverchon

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Towards a new approach in chiral resolution: Pressurized-CO2 assisted preferential cocrystallization 手性解析的新方法：加压-CO2 辅助优先共晶体化

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-24 DOI: 10.1016/j.supflu.2024.106339

Joséphine de Meester , Patrick Layrisse , Mathieu Marchivie , Laurent Collard , Guillaume Wery , Clément Brandel , Yohann Cartigny , Pascale Subra-Paternault , Tom Leyssens , Christelle Harscoat-Schiavo

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Encapsulation of Arthrospira platensis polyphenolic extract using supercritical emulsion-based process 利用超临界乳液法封装节肢动物多酚提取物

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-21 DOI: 10.1016/j.supflu.2024.106335

Chiara Bufalini , Ida Palazzo , Alessandro Alberto Casazza , Pier Francesco Ferrari , Roberta Campardelli , Giuseppe Firpo , Patrizia Perego , Ernesto Reverchon

{"title":"Encapsulation of Arthrospira platensis polyphenolic extract using supercritical emulsion-based process","authors":"Chiara Bufalini , Ida Palazzo , Alessandro Alberto Casazza , Pier Francesco Ferrari , Roberta Campardelli , Giuseppe Firpo , Patrizia Perego , Ernesto Reverchon","doi":"10.1016/j.supflu.2024.106335","DOIUrl":"https://doi.org/10.1016/j.supflu.2024.106335","url":null,"abstract":"<div>Arthrospira platensis polyphenolic natural extracts have several benefits for human health. Due to their instability and reduced shelf-life, these extracts are usually encapsulated. This work analyzed the supercritical emulsion extraction (SEE) process for the production of polymeric nanoparticles loaded with A. platensis polyphenolic extracts. The objective of this work was to evaluate a powdered encapsulation system to overcome the drawbacks of liquid systems, which are those mainly used for microalgae extract stabilization. An optimization study was performed investigating different process parameters and comparing the obtained particles in terms of particle size distribution, morphology, and encapsulation efficiency. The process permitted the successfull production of loaded polymeric nanoparticles with an encapsulation efficiency up to 74 % in the best operating conditions. The SEE process allowed a better control of morphology and particle size distribution of the nanometric particles operating in a continuous mode.</div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"212 ","pages":"Article 106335"},"PeriodicalIF":3.4,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141543023","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}

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Corrosion characteristics of Fe, Ni and Ti based alloys near the critical point of water and during supercritical water gasification and oxidation of municipal sludge 铁、镍和钛基合金在水临界点附近以及在超临界水气化和城市污泥氧化过程中的腐蚀特性

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-20 DOI: 10.1016/j.supflu.2024.106337

Lili Qian , Wenyu Ma , Dan Fang , Yanmeng Gong , Weijing Liu , Shuang Wang , Shuzhong Wang

{"title":"Corrosion characteristics of Fe, Ni and Ti based alloys near the critical point of water and during supercritical water gasification and oxidation of municipal sludge","authors":"Lili Qian , Wenyu Ma , Dan Fang , Yanmeng Gong , Weijing Liu , Shuang Wang , Shuzhong Wang","doi":"10.1016/j.supflu.2024.106337","DOIUrl":"10.1016/j.supflu.2024.106337","url":null,"abstract":"<div>Supercritical water gasification (SCWG) and oxidation (SCWO) were promising technologies for treating municipal sludge; however, corrosion hindered their development. To obtain the candidate material for preheaters, corrosion characteristics of 316, 316 L, Incoloy 800, 825, and TA-10 were investigated at 350 °C and 400 °C. For SCWG and SCWO reactors, corrosion behaviors of 316, Incoloy 800, 825, Inconel 600, 625, and Hastelloy C276 were explored at 450 °C and 520 °C, with and without oxidants. Near the critical point of water, corrosion rates of all materials were below 0.4 mm·a−1, with 316 L being the candidate material. According to the pH variation, materials underwent activation (350 °C) and passivation (400 °C) pathways. During SCWG and SCWO, Incoloy 825 and Inconel 625 were prioritized at 450 ℃ and 520 ℃, exhibiting corrosion rates below 0.40 mm·a−1 and 0.50 mm·a−1, respectively. Chemical corrosion dominated and double-layer oxide films (Fe3O4-FeCr2O4 and NiO-Cr2O3) formed.</div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"212 ","pages":"Article 106337"},"PeriodicalIF":3.4,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141464171","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}

引用次数: 0

Generalization of the Wong-Sandler mixing rule to a generic cubic equation of state: Examples of use for systems of industrial interest (Hydrogen, CCUS, refrigeration) 将 Wong-Sandler 混合规则推广到通用立方状态方程：工业系统（氢气、CCUS、制冷）应用实例

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-19 DOI: 10.1016/j.supflu.2024.106336

Salaheddine Chabab , Christophe Coquelet , Fabien Rivollet

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Facile fabrication of lightweight and high expanded TPU/PBS bead blend foam with segregated microcellular network for reduced shrinkage and enhanced interface bonding 轻松制造具有隔离微孔网络的轻质高膨胀热塑性聚氨酯/PBS 珠状混合物泡沫，以减少收缩并增强界面粘合力

IF 3.4 3区工程技术

Journal of Supercritical Fluids Pub Date : 2024-06-14 DOI: 10.1016/j.supflu.2024.106334

Fengkun Sun, Minghao Zhou, Feifan Yi, Haokun Wang, Binyi Chen, Xiangfang Peng, An Huang

{"title":"Facile fabrication of lightweight and high expanded TPU/PBS bead blend foam with segregated microcellular network for reduced shrinkage and enhanced interface bonding","authors":"Fengkun Sun, Minghao Zhou, Feifan Yi, Haokun Wang, Binyi Chen, Xiangfang Peng, An Huang","doi":"10.1016/j.supflu.2024.106334","DOIUrl":"10.1016/j.supflu.2024.106334","url":null,"abstract":"<div>The emergence of expanded thermoplastic polyurethane foam beads (ETPU) has expanded the application range of polymer foam materials. However, most of the prepared bead foam products suffer from high shrinkage rate, high density, and poor interfacial bonding, severely affecting the mechanical stability and lightweighting of the products. Herein, this study constructed thermoplastic polyurethane/polybutylene succinate (TPU/PBS) bead blend foams with a segregated microcellular network structure (SMNS) for the first time, where the TPU/PBS continuous phase formed the SMNS and the bead phase was consisted of TPU foam beads. The results showed good interfacial bonding between the continuous and bead phases. By adding PBS to the continuous phase, the shrinkage percentage of TPU/PBS bead blend foam decreased from 79.19 % to 67.31 %, reduced by 15.0 %. In addition, the foam expansion ratio gradually decreased with increasing PBS content, dropping from 12.07 to 9.03. Moreover, TPU/PBS bead blend foams exhibited good energy absorption and mechanical stability without sacrificing thermal insulation performance. This work effectively reduced the shrinkage of TPU based foam materials, offering a simple and economical solution for the preparation of dimensionally stable, well-interfaced, and lightweight polymer foams.</div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"212 ","pages":"Article 106334"},"PeriodicalIF":3.4,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141395491","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}

引用次数: 0