Journal of Supercritical Fluids最新文献

{"title":"Correlating mean particle size of pure solids in supercritical antisolvent processes using dimensional analysis with the Buckingham π-theorem","authors":"Juan C. de la Fuente ,&nbsp;Yusuke Shimoyama","doi":"10.1016/j.supflu.2024.106512","DOIUrl":"10.1016/j.supflu.2024.106512","url":null,"abstract":"<div><div>In supercritical antisolvent processes, two correlations have been proposed to estimate the mean particle size of precipitated pure solid compounds. These easy-to-use correlations, each with six adjustable coefficients were developed by applying dimensional analysis based on the Buckingham π-theorem, relating the particle size to feeding, thermodynamic, and mechanical process parameters. These correlations can help in scaling-up microparticle production processes; however, they do not conceptually explain the influence of process parameters on particle sizes, and remain limited by the experimental available data. The two correlations are differentiated by employing either solute supersaturation data or molar volumes of CO₂+solvent systems. These correlations were evaluated by testing seventeen ternary systems, with deviations from experimental values ≤ 88 %. They proved capable of correlating all solutes grouped by the same solvent. Pilot-scale data were estimated using coefficients adjusted with laboratory-scale data. Finally, the correlations successfully reproduced the particle size as a function of temperature and pressure.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106512"},"PeriodicalIF":3.4,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990546","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":"Continuous biodiesel production using canola oil and supercritical methanol with the aid of CaO/carbon nanotube catalyst","authors":"Chin Seng Liew ,&nbsp;Ken Furuta ,&nbsp;Mohammed Ahmed Mohammed Ali ,&nbsp;Yukihiko Matsumura","doi":"10.1016/j.supflu.2025.106515","DOIUrl":"10.1016/j.supflu.2025.106515","url":null,"abstract":"<div><div>A catalyst can improve the rate of supercritical transesterification, thereby reducing the construction costs of the reactor. Although calcium oxide (CaO) is an effective catalyst, it has low stability and requires a support structure. Multiwall carbon nanotubes (MWCNTs) have high porosity, large specific surface area, and high tensile strength, and could serve as support structures. Therefore, this study elucidated the effectiveness of a CaO-impregnated MWCNT catalyst in accelerating the supercritical transesterification process. A 40 wt% of CaO was the optimal concentration for impregnation onto CNTs for transesterification in supercritical methanol under the following conditions: 300 °C, 20 MPa, methanol to oil molar ratio of 40:1, WHSV of 100 h⁻¹. The fatty acid methyl esters yield of the supercritical methanol transesterification process reached 1.0 under these conditions; additionally, the yield was maintained for 6 h. The reaction was well described by the first-order reaction rate of the homogeneous and heterogeneous reactions.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106515"},"PeriodicalIF":3.4,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968069","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":"Advances and trends in compressed fluid extraction to recovering bioactive compounds from avocado: Effect of extraction parameters, biological properties, and applications","authors":"Diego Fernando García-Ramón ,&nbsp;Jaime Valdiviezo-Marcelo ,&nbsp;Christianne Elisabete da Costa Rodrigues ,&nbsp;Juliane Viganó ,&nbsp;Alessandra Lopes de Oliveira","doi":"10.1016/j.supflu.2024.106505","DOIUrl":"10.1016/j.supflu.2024.106505","url":null,"abstract":"<div><div>Avocado is widely recognized for its rich nutritional profile and as a valuable source of bioactive compounds with well-established health benefits. Traditional extraction methods, however, often involve the use of harmful solvents, extended processing times, and high temperatures, which can degrade heat-sensitive compounds. To overcome these challenges, advanced extraction techniques such as pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE) have been employed to efficiently recover bioactive compounds from avocado. This review evaluates the performance of these techniques and examines key process variables, including temperature, pressure, solvent flow rate, solvent-to-feed mass ratio (S/F), the use of co-solvents, particle size, and moisture content. Additionally, it explores the biological properties of the extracts and their potential applications. The findings highlight that PLE and SFE are highly effective in extracting a diverse range of bioactive compounds, including polyphenols, unsaturated fatty acids, tocopherols, and carotenoids. These extracts exhibit notable anticancer, antidiabetic, antioxidant, and antimicrobial activities. The advantages of these methods include reduced extraction times, lower solvent consumption, and improved preservation of thermolabile compounds. However, the high cost of equipment remains a significant drawback for industrial-scale implementation. In conclusion, PLE and SFE represent sustainable and efficient strategies for the comprehensive valorization of avocado, with significant potential for the development of high-value natural ingredients. Future research should focus on multiparametric process optimization, assessment of industrial scalability, extensive in vivo studies, the creation of specific applications across various industries, and comparative sustainability analyses against conventional methods.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106505"},"PeriodicalIF":3.4,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990551","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":"Measurements and prediction of dynamic viscosity of binary mixtures of carbon dioxide and methanol, ethanol and 1-propanol at 313–343 K and 15–30 MPa","authors":"Norihiro Onodera,&nbsp;Ryuichi Oguro,&nbsp;Toshitaka Funazukuri","doi":"10.1016/j.supflu.2024.106514","DOIUrl":"10.1016/j.supflu.2024.106514","url":null,"abstract":"<div><div>The dynamic viscosity <em>η</em>_m of binary mixtures of carbon dioxide and methanol/1-propanol was measured on the basis of the pressure drop in a packed bed, which was calculated using the Ergun equation, at temperatures from 313.2 K to 343.2 K and pressures from 15 MPa to 30 MPa over the entire range of methanol/1-propanol composition. The accuracy of the rough-hard-sphere (RHS) model with various combining rules was tested and compared with that of the Eyring theory with the perturbed-chain SAFT (PC-SAFT) equation of state (EoS) model the authors proposed previously. The average relative deviations (ARD) of the RHS model with the Fender-Halsey combining rule and the interaction parameter value adjusted were 5.0 % (max.RD: 23 %), for 240 sets of conditions over the entire range of methanol/ethanol/1-propanol compositions, as compared with 6.3 % (max.RD: 26 %) of the Eyring theory with PC-SAFT EoS model with the optimized <em>k</em>_Eyring value.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106514"},"PeriodicalIF":3.4,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142990560","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":"Asymptotic Widom line of supercritical fluid within the scaling theory","authors":"M.Yu. Belyakov,&nbsp;V.D. Kulikov","doi":"10.1016/j.supflu.2024.106513","DOIUrl":"10.1016/j.supflu.2024.106513","url":null,"abstract":"<div><div>The work is devoted to a theoretical study of fluid thermodynamic features in the supercritical region. The analysis is carried out within the framework of the scaling theory based on the general equation of state of a near-critical fluid. Analytical expressions for fluid characteristics lines on the pressure–temperature plane are obtained. It is shown that close to the critical point the characteristic lines come closer forming the so-called single Widom line. An analytical expression is formulated for the asymptotic Widom line, as a common part of fluid characteristics. These line tracks are found to depend on the initial scaling concept. Widom line turns out to be closest to the critical isochore and is directly related to the coexistence curve of the near-critical fluid. To illustrate the results, asymptotic lines of methane, n-pentane, carbon dioxide, and water are constructed based on the NIST simulator numerical data.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106513"},"PeriodicalIF":3.4,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968070","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":"Ibuprofen loaded gelatin-siloxane gels prepared by supercritical CO2-assisted impregnation/deposition for controlled drug release and tissue engineering","authors":"Ulisses Silva do Nascimento ,&nbsp;Carolina Kafka Neves ,&nbsp;Erik Felix dos Santos ,&nbsp;Chekwube Andrew Ezegbe ,&nbsp;Laurent Rodrigues Rezende ,&nbsp;Juliana Marchi ,&nbsp;Christiane Bertachini Lombello ,&nbsp;Lígia Passos Maia-Obi","doi":"10.1016/j.supflu.2024.106511","DOIUrl":"10.1016/j.supflu.2024.106511","url":null,"abstract":"<div><div>Gelatin-based gels are suitable for biomedical applications and have potential to be impregnated using scCO₂ thanks mainly to their morphology. Aiming to obtain ibuprofen loaded gelatin-siloxane cryogels suitable for controlled drug release and tissue engineering, the impregnation/deposition of the drug was studied in both cryogels and xerogels in scCO₂ at 25 MPa and 35 °C, by varying its concentrations and the amount of co-solvent. The obtained samples were evaluated by FTIR, SEM, drug release and cytotoxicity studies. For the xerogels, the ibuprofen dispersed in the matrix, while for cryogels, additionally, it was deposited as flake-like particles inside their pores, thus presenting a higher drug load. Increasing the ibuprofen concentration and using 3 %v/v of co-solvent, increases the drug load. An extended release was observed for gels with sufficient drug load and no significative cytotoxicity was observed, showing that these gels can be applied as multifunctional scaffolds.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106511"},"PeriodicalIF":3.4,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968071","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":"Precipitation of micro and nanosilica and PdO/silica particles from SEDS technique using supercritical CO2","authors":"Alexander Junges ,&nbsp;Thais Feiden ,&nbsp;Bruno Fischer ,&nbsp;Marcos Hiroiuqui Kunita ,&nbsp;Silvana Mattedi ,&nbsp;Claudio Dariva ,&nbsp;Silvia Maria Egues ,&nbsp;Eunice Valduga ,&nbsp;Elton Franceschi","doi":"10.1016/j.supflu.2024.106507","DOIUrl":"10.1016/j.supflu.2024.106507","url":null,"abstract":"<div><div>This study utilized the Solution-Enhanced Dispersion by Supercritical Fluids (SEDS) technique to precipitate micro and nanosilica and PdO/silica composites using supercritical CO₂ as an anti-solvent and an ionic liquid as an adjuvant. Unlike previous studies, this work uniquely combines the sol-gel process with supercritical CO₂ technology, introducing ionic liquids to significantly enhance the surface area (up to 38-fold) and structural integrity of the silica particles. A detailed factorial experimental design was implemented to optimize key parameters such as temperature, CO₂ flow rate, and ionic liquid concentration, leading to the controlled synthesis of uniform nanoparticles and stable PdO/silica composites. The findings highlight the potential of this SEDS technique for advancements in materials science, catalysis, drug delivery, and environmental technology.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106507"},"PeriodicalIF":3.4,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929294","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":"Sequential extraction of industrial spent coffee grounds using pressurized fluids as solvents","authors":"Akel F. Kanaan,&nbsp;Kallynca C. dos Santos,&nbsp;Maria A.H. Menezes,&nbsp;Fabiane Hamerski,&nbsp;Fernando A.P. Voll,&nbsp;Marcos L. Corazza","doi":"10.1016/j.supflu.2024.106503","DOIUrl":"10.1016/j.supflu.2024.106503","url":null,"abstract":"<div><div>This study explores the sequential extraction of valuable compounds from industrial spent coffee grounds (SCG) using sustainable pressurized fluid methods: compressed propane (CPE), pressurized liquid extraction (PLE), and supercritical CO₂ with ethanol (coscCO₂). The extracts were analyzed for yield, fatty acid profile, total phenolic content (TPC), and antioxidant activity (AA). Sequential extractions increased the total extraction yield by up to 9.0 % and 6.2 % when PLE or coscCO₂ followed CPE, respectively. Optimal conditions were PLE at 80°C, 100 bar, 6 mL/min, yielding 6258 ± 521 mg GAE.100/g TPC and 22957 ± 206 µmol TE.100/g AA, and coscCO₂ at 80°C, 200 bar, 2 mL/min, yielding 2154 ± 56 mg GAE.100/g TPC and 4196 ± 140 µmol TE.100/g AA. These results highlight the efficiency of sequential extraction for recovering bioactive compounds from SCG, promoting sustainable waste valorization.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106503"},"PeriodicalIF":3.4,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929237","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":"A novel approach to investigating the relation between color strength and relative dye concentration and to controllably modifying the color strength of dyed polyester fabrics through supercritical fluid treatment","authors":"Jianhua Ren ,&nbsp;Mitsuru Mizuno ,&nbsp;Isao Tabata ,&nbsp;Teruo Hori ,&nbsp;Kazumasa Hirogaki","doi":"10.1016/j.supflu.2024.106504","DOIUrl":"10.1016/j.supflu.2024.106504","url":null,"abstract":"<div><div>Widely utilized polyester fibers generally have excellent color fastness, making it quite challenging to controllably modify their color strength (<em>K</em>/<em>S</em> value), especially in regulated decolorization. In this study, the relation between the color strength and the relative dye concentration of dyed polyester fabrics was investigated based on the principle that dyes may migrate and reach redistribution equilibrium through supercritical carbon dioxide fluid treatment. The results demonstrated that the relation agreed well with an exponential decay fitting, allowing for the controllable modification of the color strength of dyed polyester fabrics using the derived regression formulas. Furthermore, the correlation between the residual dye in the supercritical fluid treatment vessel and the color strength of the previously treated fabric was clarified. To verify the universality of the above strategies, three dyes with representative anthraquinone, heterocyclic, and azo structures were employed in this study. Furthermore, it was observed that the dyes were evenly diffused throughout the polyester fibers following the supercritical fluid treatment, promising the fibers’ good color fastness. These findings might be significant for exploring the dyeing behavior of fibers in supercritical fluids, stimulating the reutilization of colored polyester and carbon neutrality of textiles, and expanding the potential applications of supercritical fluid technology.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106504"},"PeriodicalIF":3.4,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929236","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}

{"title":"Supercritical CO2 impregnation of nanodiamonds into polymethylmethacrylate film and the film’s optical property","authors":"Jinhua Hu,&nbsp;Kunitoyo Osawa,&nbsp;Kaoru Tada,&nbsp;Kentaro Taki,&nbsp;Hirohisa Uchida,&nbsp;Kazuhiro Tamura","doi":"10.1016/j.supflu.2024.106506","DOIUrl":"10.1016/j.supflu.2024.106506","url":null,"abstract":"<div><div>The supercritical CO₂ (scCO₂) impregnation of nanodiamond (ND) in polymethylmethacrylate (PMMA) film was carried out over the pressure ranges of 12 MPa to 20 MPa and temperatures of 40 °C to 100 °C. The amount of ND impregnated in ND-PMMA composite film, and the refractive indices of the film were investigated. The refractive index increased linearly with the amount of ND accumulated in the film. The morphology on the surface and inside of the ND-PMMA composite film was characterized by SEM, TEM, AFM, and FT-IR analysis. The ND-PMMA film surface after scCO₂ treatment was smoother than before scCO₂ treatment, and the ND particles were embedded into the PMMA matrix and uniformly distributed near the interior of the film surface. The results of the retardation and birefringence of the ND-impregnated PMMA film after scCO₂ treatment indicated that ND impregnation of PMMA film enhances the optical anisotropy of the original PMMA film.</div></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":"218 ","pages":"Article 106506"},"PeriodicalIF":3.4,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929234","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}