Selective extraction of bioactive compounds from annatto seeds by sequential supercritical CO2 process
Publication date: Available online 23 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Renata Vardanega, Gislaine C. Nogueira, Carla D.O. Nascimento, Adelia F. Faria-Machado, M. Angela A. MeirelesAbstractThe present work proposed a two-step sequential scCO2 extraction process to selectively extract the main bioactive compounds from annatto seeds, geranylgeraniol and tocols, aiming to diversify and to improve the added-value of annatto seeds products. Firstly, pressure (10, 17, 24 and 31 MPa) and temperature (40 and 60 °C) conditions resulting CO2 densities ranging from 290 kg/m3 to 9...
Source: The Journal of Supercritical Fluids - April 25, 2019 Category: Chemistry Source Type: research

Exfoliation of layered yttrium hydroxide by rapid expansion of supercritical suspensions
Publication date: Available online 22 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Alexey D. Yapryntsev, Konstantin B. Ustinovich, Anfisa A. Rodina, Vasiliy A. Lebedev, Oleg I. Pokrovskiy, Khursand E. Yorov, Andrey V. Gavrikov, Alexander E. Baranchikov, Vladimir K. IvanovAbstractRapid expansion of supercritical suspensions was used for the first time to push apart the layers in a layered metal hydroxide structure. Treatment with supercritical CO2 resulted in significant changes in interlayer distances in yttrium hydroxide intercalated with dodecyl sulfate anions. According to XRD, SEM, TEM, nitrogen adso...
Source: The Journal of Supercritical Fluids - April 23, 2019 Category: Chemistry Source Type: research

Fabrication, characterization, and in vitro evaluation of biomimetic silk fibroin porous scaffolds via supercritical CO2 technology
In this study, silk fibroin (SF) scaffolds with interconnected porous and ECM-like nanofibrous structures were prepared by successfully combining supercritical CO2 technology with a porogen leaching process. The effects of pressure and concentration of the SF solution on the nanofibrous structures of the SF scaffolds were not significant. By manipulating the proportion of porogen, SF scaffolds with a porosity of (32.7 ± 1.7) % to (82.1 ± 2.3) % and a mechanical strength of (237.0 ± 2.2) kPa to (163.0 ± 6.5) kPa were fabricated. In vitro biocompatibility evaluation using a MTT assay, DAPI stainin...
Source: The Journal of Supercritical Fluids - April 23, 2019 Category: Chemistry Source Type: research

Alginate and hybrid alginate-hyaluronic acid aerogel microspheres as potential carrier for pulmonary drug delivery
Publication date: Available online 22 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Tamara Athamneh, Adil Amin, Edit Benke, Rita Ambrus, Claudia S. Leopold, Pavel Gurikov, Irina SmirnovaAbstractThe aim of the present study was the preparation of aerogel microspheres based on alginate and hyaluronic acid for the potential application in pulmonary drug delivery. Both polymers are commonly used in the pharmaceutical and medical fields because of their nontoxicity, biodegradability and biocompatibility characteristics. The bio-based microspheres were produced using an emulsion gelation process with a subseque...
Source: The Journal of Supercritical Fluids - April 23, 2019 Category: Chemistry Source Type: research

Use of heterogeneous acid catalyst combined with pressurized conditions for esters production from macauba pulp oil and methyl acetate
The objective of this work was to evaluate the production of fatty acid methyl esters using macauba oil and methyl acetate under pressurized conditions, using heterogeneous γ-alumina catalyst in a continuous system. The catalytic reaction kinetics were evaluated at temperatures between 225 and 300 °C, as well as the effect of catalyst particle size on the reaction. The temperature increase promoted an esters and triacetin (TA) production rise. It was found that the catalyst utilization, in granulometry from 0.85 to 1.00 mm, allowed better product yields at shorter residence time. The best result for catalytic rea...
Source: The Journal of Supercritical Fluids - April 22, 2019 Category: Chemistry Source Type: research

Composition and physical properties of babassu seed (Orbignya phalerata) oil obtained by supercritical CO2 extraction
Publication date: Available online 18 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Naila Albertina de Oliveira, Mônica Roberta Mazzali, Heidge Fukumasu, Cintia Bernardo Gonçalves, Alessandra Lopes de OliveiraAbstractOil was obtained from babassu seeds via supercritical CO2 extraction under conditions from 40 to 80 °C and at pressures of 25 to 35 MPa. The fatty acid profile was determined by gas chromatography–mass spectrometry (GC-MS), and the triacylglycerol (TAG) composition was estimated. The highest oil recoveries from the seeds, 86.56% and 89.86%, were obtained b...
Source: The Journal of Supercritical Fluids - April 20, 2019 Category: Chemistry Source Type: research

Experimental measurement of solubilities of sertraline hydrochloride in supercriticalcarbon dioxide with/without menthol: Data correlation
Publication date: July 2019Source: The Journal of Supercritical Fluids, Volume 149Author(s): Gholamhossein Sodeifian, Seyed Ali SajadianAbstractFor the first time, the solubilities of sertraline hydrochloride in SC-CO2, as a binary system, and SC-CO2 + menthol, as a ternary system, were determined. Experimental data was achieved at 308, 318, 328 and 338 K at different pressures ranging from 12 to 30 MPa. The solubility of sertraline in the binary system was found to range from 0.100 × 10−5 to 0.930 × 10−4 mole fractions, while that in the ternary system exhi...
Source: The Journal of Supercritical Fluids - April 17, 2019 Category: Chemistry Source Type: research

Liquefaction of Waste Hazelnut Shell by Using Sub- and Supercritical Solvents as a Reaction Medium
Publication date: Available online 15 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Emre Demirkaya, Orkan Dal, Aslı YükselAbstractDirect thermochemical biomass degradation to obtain bio-oil by using organic solvents is not a new process type, and it has some advantages over hydrothermal liquefaction technique. However, up to our best knowledge, in this study, hazelnut shell decomposition by using ethanol, acetone and their mixtures at sub/supercritical conditions was studied for the first time in literature. Experiments were carried out between 220-300 °C, at three different reaction time...
Source: The Journal of Supercritical Fluids - April 16, 2019 Category: Chemistry Source Type: research

Extraction of vetiver (Chrysopogon zizanioides) root oil by supercritical CO2, pressurized-liquid, and ultrasound-assisted methods and modeling of supercritical extraction kinetics
In this study, non-conventional methods of supercritical extraction with CO2 as well as with ethanol or ethyl acetate cosolvent, pressurized-liquid extraction (PLE), and ultrasound-assisted extraction (UAE) were employed to evaluate the extraction of vetiver (Chrysopogon zizanioides) oil in comparison with hydrodistillation and Soxhlet techniques. The highest yields by supercritical CO2 extraction were obtained at 60 °C and 20 MPa, 2.23 % (m/m), and 2.66 % (m/m) with 5 % (V/V) of ethanol cosolvent, while PLE and UAE methods allowed a reduction of the time and solvent volume, obtaining up to 83 % and 70 % ...
Source: The Journal of Supercritical Fluids - April 14, 2019 Category: Chemistry Source Type: research

Structure-tunable thermoplastic polyurethane foams fabricated by supercritical carbon dioxide foaming and their compressive mechanical properties
This study is of great significance in enriching the understanding of both the foaming behavior of TPU and the structure-property relationships of TPU foams.Graphical abstract (Source: The Journal of Supercritical Fluids)
Source: The Journal of Supercritical Fluids - April 11, 2019 Category: Chemistry Source Type: research

Preparation of Balangu (Lallemantia royleana) seed mucilage aerogels loaded with paracetamol: evaluation of drug loading via response surface methodology
Publication date: Available online 11 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Mohammad Taghi Falahati, Seyyed M. GhoreishiAbstractIn this work, paracetamol (PCM) loading into Balangu seed mucilage (BSM) aerogels was investigated using the combination of supercritical drying and gas antisolvent (GAS) precipitation method. Response surface methodology (RSM) was implemented for the modeling and optimization of drug loading into the aerogel matrix. The temperature (40-60 °C), pressure (8-24 MPa) and drug solution concentration (0.2-0.6 Molar) were considered as the range of oper...
Source: The Journal of Supercritical Fluids - April 11, 2019 Category: Chemistry Source Type: research

High pressure phase behaviour for the CO2 + n-dodecane + 3,7-dimethyl-1-octanol system
Publication date: Available online 8 April 2019Source: The Journal of Supercritical FluidsAuthor(s): C. Latsky, N.S. Mabena, C.E. SchwarzAbstractIn this work, the solute-solute interaction which exist in the CO2 + n-dodecane+ 3,7-dimethyl-1-octanol system was investigated. Solubility data were measured for three mixtures containing solvent free n-dodecane fractions of 0.50, 0.75 and 0.85, between 308 K and 348 K and pressures up to 14.9 MPa, with solvent mass fractions ranging from 0.375 to 0.984, using a static synthetic method. The data revealed significant solute-solute interactions, which resulted ...
Source: The Journal of Supercritical Fluids - April 10, 2019 Category: Chemistry Source Type: research

A heat transfer - friction analogy for fluids at supercritical pressure
Publication date: Available online 10 April 2019Source: The Journal of Supercritical FluidsAuthor(s): J.W.R. Peeters, M. RohdeAbstractA new friction-heat transfer analogy for the prediction of heat transfer to turbulent fluids at supercritical pressure is presented. This analogy is based on the observation that the predominent events that determine the turbulent heat flux known as hot ejections and cold sweeps have different thermophysical properties. This observation is used to derive a new friction-heat transfer analogy, which we call the ejection-sweep analogy. It is shown that the ejection-sweep analogy yields very goo...
Source: The Journal of Supercritical Fluids - April 10, 2019 Category: Chemistry Source Type: research

Supercritical carbon dioxide fractionation of bio-crude produced by hydrothermal liquefaction of pinewood
Publication date: Available online 4 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Nikolaos Montesantos, Thomas Helmer Pedersen, Rudi Pankratz Nielsen, Lasse Rosendahl, Marco MaschiettiAbstractThe supercritical carbon dioxide extraction of bio-crude, produced by hydrothermal liquefaction of lignocellulosic biomass, was investigated for pressures and temperatures in the range 112 to 400 bar and 40 to 120 °C, corresponding to solvent densities in the range 548 to 882 kg/m3. Total extraction yields ranged from 17 to 42%. For a given solvent density, temperature increase drastically i...
Source: The Journal of Supercritical Fluids - April 5, 2019 Category: Chemistry Source Type: research

Silicone aerogels with tunable mechanical properties obtained via hydrosilylation reaction in supercritical CO2
Publication date: Available online 4 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Igor V. Elmanovich, Tatyana A. Pryakhina, Marat O. Gallyamov, Dmitry A. Migulin, Ivan B. Meshkov, Viktor G. Vasil’ev, Aziz M. MuzafarovAbstractIn the present work various sets of vinyl- and hydride-containing precursors are explored for aerogels synthesis via hydrosilylation route directly in supercritical CO2. The means to control the target mechanical properties of aerogels by changing the precursors composition are proposed. Aerogels with Young’s modulus as low as 3.6 kPa can be obtained using hyperbra...
Source: The Journal of Supercritical Fluids - April 5, 2019 Category: Chemistry Source Type: research

Organic solvent free preparation of porous scaffolds based on the phase morphology control using supercritical CO2
Publication date: Available online 3 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Jia Chen, Jiangang Ye, Xia Liao, Shaojie Li, Wei Xiao, Qi Yang, Guangxian LiAbstractPorous polylactide (PLA) scaffolds for tissue engineering were successfully manufactured from co-continuous PLA/polyvinyl pyrrolidone (PVP) blends by combining annealing treatment in supercritical carbon dioxide (scCO2) and porogen leaching. Based on the water solubility of PVP, the employment of organic solvents could be completely avoided during the fabrication of scaffolds. The average pore size ranges from 30 μm to 160 &...
Source: The Journal of Supercritical Fluids - April 3, 2019 Category: Chemistry Source Type: research

Development of a rapid decompression system for nanocellular foaming at 100 MPa
Publication date: July 2019Source: The Journal of Supercritical Fluids, Volume 149Author(s): Takumi Ono, Xueli Wu, Takeshi Furuya, Satoshi YodaAbstractA new foaming apparatus, which can depressurize the vessel that contains polymer + gas from 100 MPa to atmospheric pressure in 50 ms, was developed to generate a high degree of supersaturation. The influences of the saturation conditions and the molecular weight of the polymer were studied with the new rapid decompression system using the polymethyl methacrylate (PMMA) - CO2 system as a model. It is found that the Sub-micron cellular structures co...
Source: The Journal of Supercritical Fluids - April 3, 2019 Category: Chemistry Source Type: research

Experimental measurement of solubilities of sertraline hydrochloride in supercritical carbon dioxide with/without menthol: Data correlationwith a pressure of about 60
Publication date: Available online 1 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Gholamhossein Sodeifian, Seyed Ali SajadianAbstractFor the first time, the solubilities of sertraline hydrochloride in SC-CO2, as a binary system, and SC-CO2 + menthol, as a ternary system, were determined. Experimental data was achieved at 308, 318, 328 and 338 K at different pressures ranging from 12 to 30 MPa. The solubility of sertraline in the binary system was found to range from 0.100 × 10−5 to 0.930 × 10−4 mole fractions, while that in the ternary sys...
Source: The Journal of Supercritical Fluids - April 2, 2019 Category: Chemistry Source Type: research

Amidophosphonate ligands as cerium extractants in supercritical CO2
Publication date: Available online 1 April 2019Source: The Journal of Supercritical FluidsAuthor(s): Sofyane Bouali, Antoine Leybros, Guillaume Toquer, Antoine Leydier, Agnès Grandjean, Thomas ZembAbstractIndustrial-scale rare earth extraction is typically performed by liquid-liquid extraction with large amounts of solvents, acids and organophosphorus ligands. An alternative is to use these extractants in supercritical CO2 (SC-CO2), where the crucial operating parameter is their solubility. Different molecules with amidophosphonate backbones have been synthesized and investigated to improve their solubility in SC-CO...
Source: The Journal of Supercritical Fluids - April 2, 2019 Category: Chemistry Source Type: research

Mesoporous aerogel-like Al-Si oxides obtained via supercritical antisolvent precipitation of alumina and silica sols
Publication date: Available online 30 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Nikolai S. Nesterov, Anton S. Shalygin, Vera P. Pakharukova, Tatyana S. Glazneva, Oleg N. MartyanovAbstractA method of alumina and silica sols precipitation in supercritical CO2 has been developed for the first time to prepare alumina and silica doped alumina. The silicon content of samples is varied within the range from 0 to 30 mol. %. The approach suggested can be considered as a development of supercritical antisolvent (SAS) method that is widely used to prepare powders from solutions but not sols. The alumina a...
Source: The Journal of Supercritical Fluids - March 31, 2019 Category: Chemistry Source Type: research

Ifc
Publication date: June 2019Source: The Journal of Supercritical Fluids, Volume 148Author(s): (Source: The Journal of Supercritical Fluids)
Source: The Journal of Supercritical Fluids - March 31, 2019 Category: Chemistry Source Type: research

Microcellular natural rubber using supercritical CO2 technology
Publication date: Available online 29 March 2019Source: The Journal of Supercritical FluidsAuthor(s): W. Tessanan, P. Phinyocheep, P. Daniel, A. GibaudAbstractMicrocellular natural rubber (NR) prepared using a supercritical CO2 technology is a promising alternative to replace traditional foaming agent due to environmental concern. Crucial parameters for the foaming process including CO2 saturation time (30, 60, 90, 120, 180) min, pressure (0, 8.5, 10.5, 12.5) MPa, temperature (45, 55, 65, 85) °C, and crosslinking characteristics of NR (pre-vulcanized time at 15 min and 30 min) were orderly conducted. The ...
Source: The Journal of Supercritical Fluids - March 30, 2019 Category: Chemistry Source Type: research

Superhydrophobic coatings on textiles based on novel poly(perfluoro-tert-hexylbutyl methacrylate-co-hydroxyethyl methacrylate) copolymer deposited from solutions in supercritical carbon dioxide
Publication date: Available online 26 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Polina S. Kazaryan, Andrey A. Tyutyunov, Mikhail S. Kondratenko, Igor V. Elmanovich, Andrey I. Stakhanov, Vadim V. Zefirov, Marat O. Gallyamov, Inesa V. Blagodatskikh, Alexey R. KhokhlovAbstractA novel 6,6,7,7,8,8,8-Heptafluoro-5,5-bis(trifluoromethyl)octyl methacrylate monomer is synthesized. Corresponding homopolymers and copolymers with hydroxyethyl methacrylate are obtained by means of radical polymerization in supercritical carbon dioxide using azoisobutyronitrile as an initiator. The resulting homopolymers are highly...
Source: The Journal of Supercritical Fluids - March 27, 2019 Category: Chemistry Source Type: research

Comprehensive analysis and quality assessment of Herba Epimedii from multiple botanical origins based on ultra-high performance supercritical fluid chromatography coupled with quadrupole time-of-flight mass spectrometry and photodiode array detector
Publication date: Available online 25 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Xinguang Sun, Jie Yang, Yang Zhao, Wei Zheng, Xu Pang, Bei Wang, Jie Wang, Qi Li, Xiaojuan Chen, Jie Zhang, Qianzhi Ding, Yunbo Sun, Dawei Liu, Dabing Zhang, Shuchen Liu, Baolin Guo, Baiping MaABSTRACTHerbal medicines (HMs) usually consist of complex matrices of phytochemical compounds responsible for their efficacy. Supercritical fluid chromatography (SFC) and ultra-high performance SFC (UHPSFC) are efficient techniques that can be advantageously used for the analysis complex HMs. Here, the comprehensive UHPSFC methods we...
Source: The Journal of Supercritical Fluids - March 27, 2019 Category: Chemistry Source Type: research

Utilization of pressurized CO2, pressurized ethanol and CO2-expanded ethanol mixtures for de-oiling spent bleaching earths
Publication date: Available online 25 March 2019Source: The Journal of Supercritical FluidsAuthor(s): P. Subra-Paternault, C. Harscoat-Schiavo, R. Savoire, M. Brun, J. Velasco, V. Ruiz-MendezAbstractCompressed fluids were used in a two-step scheme to extract oil from rapeseed and sunflower spent bleaching earths. The first extraction, performed with CO2 at 45 °C, 23 MPa, yielded matrices depleted in neutral lipids (contents of 1% and 3.5% compared to initial 22% and 28%) and of better flowing characteristics thanks to the downsizing of particle (83% of particles had sizes below 50 μm). The second step ...
Source: The Journal of Supercritical Fluids - March 27, 2019 Category: Chemistry Source Type: research

Development of a Rapid Decompression System for Nanocellular Foaming at 100 MPa
Publication date: Available online 22 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Takumi Ono, Xueli Wu, Takeshi Furuya, Satoshi YodaAbstractA new foaming apparatus, which can depressurize the vessel that contains polymer + gas from 100 MPa to atmospheric pressure in 50 ms, was developed to generate a high degree of supersaturation. The influences of the saturation conditions and the molecular weight of the polymer were studied with the new rapid decompression system using the polymethyl methacrylate (PMMA) - CO2 system as a model. It is found that the Sub-micron cellular stru...
Source: The Journal of Supercritical Fluids - March 24, 2019 Category: Chemistry Source Type: research

Analysis of the Antitumor Activity of Bioactive Compounds of Cannabis Flowers Extracted by Green Solvents
Publication date: Available online 21 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Daniel Ribeiro Grijó, Danielle Lazarin Bidoia, Celso Vataru Nakamura, Ignacio Vieitez Osorio, Lúcio Cardozo-FilhoAbstractThe inhibitory effects of Cannabis flower extracts, obtained by supercritical carbon dioxide (scCO2) with and without modifier, on various human tumour cells and non-tumour cells were evaluated. Different techniques were used to optimize the polarity interaction between solute and solvent before extraction. An increase in the cannabinoid content of interest (CBD/THC) was evaluated by decarb...
Source: The Journal of Supercritical Fluids - March 22, 2019 Category: Chemistry Source Type: research

Integrated extraction approach to increase the recovery of antioxidant compounds from Sida rhombifolia leaves
Publication date: Available online 21 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Diego Márlon Ferro, Simone Mazzutti, Luciano Vitali, Carmen Maria Oliveira Müller, Sandra Regina Salvador FerreiraAbstractIntegrated downstream processes, combining Supercritical Fluid Extraction (SFE) with Pressurized Liquid Extraction (PLE), were used to recover antioxidants from Sida rhombifolia leaves. The SFE depressurization step was evaluated to improve PLE efficiency in the recovery of phenolic compounds. Total phenolic content of the extracts was performed by Folin-Ciocalteu method, and in vitro antiox...
Source: The Journal of Supercritical Fluids - March 22, 2019 Category: Chemistry Source Type: research

Supercritical Anti-solvent Process as an Alternative Technology for Vitamin Complex Encapsulation Using Zein as Wall Material: Technical-economic Evaluation
The objective of this study was to investigate the technical-economic feasibility of supercritical antisolvent technique for the precipitation of a vitamin complex containing riboflavin, δ-tocopherol and β-carotenein zein microcapsules. First, the following parameters were investigated for the precipitation of pure zein: pressure (7.0–16.0 MPa), anti-solvent flow rate (20–60 g/min), solution flow ratio (0.5–1.5 mL/min) and concentration of zein in an aqueous ethanol solution (0.02–0.04 g/mL). At optimized SAS condition for zein precipitation (pressure of 16&thi...
Source: The Journal of Supercritical Fluids - March 21, 2019 Category: Chemistry Source Type: research

A simple method for preparation of silica Aerogels Doped with monodispersed nanoparticles in homogeneous concentration
Publication date: Available online 16 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Guy Lazovski, Galit Bar, JI Botao, Nurit Atar, Uri Banin, Raz GvishiAbstractSilica aerogel is a solid matrix, capable of preserving the unique properties of nanoparticles incorporated in it; forming a macroscopic structure that benefits from nano-metric properties.We developed a simple method for preparation of doped silica aerogels. Dopants are implemented as silica coated nanoparticles suspended in alcohol or alcohol:water mixture. This suspension replaces a portion of the pure solvent in the one-step base catalyzed sili...
Source: The Journal of Supercritical Fluids - March 16, 2019 Category: Chemistry Source Type: research

Ifc
Publication date: May 2019Source: The Journal of Supercritical Fluids, Volume 147Author(s): (Source: The Journal of Supercritical Fluids)
Source: The Journal of Supercritical Fluids - March 15, 2019 Category: Chemistry Source Type: research

New developments in the modelling of carotenoids extraction from microalgae with supercritical CO2
Publication date: Available online 9 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Helena Sovová, Roumiana P. StatevaAbstractLiterature data on the extraction of carotenoids from microalgae with supercritical carbon dioxide (scCO2) were used to describe the process as an extraction of a solution of carotenoids in oil. A mathematical model for oil extraction from microalgae, including also the adsorption on microalgal surfaces, was extended for this purpose. The working hypothesis was that the extraction process is primarily controlled by phase equilibrium where the solubility of carotenoids in scCO...
Source: The Journal of Supercritical Fluids - March 11, 2019 Category: Chemistry Source Type: research

Stabilization of 4FS(EO)2 constructed water-in-carbon dioxide microemulsions (W/C μEs) with nonfluorinated co-surfactants
Publication date: Available online 7 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Lei Bao, Yang Chen, Liru Ma, Dongdong Hu, Yuan Zong, Ling Zhao, Weikang Yuan, Tao LiuAbstractThree nonfluorinated co-surfactants, sodium bis (2-(isopropoxy)-ethanol) sulfonate (di-IOESS), sodium bis (3,5,5-trimethyl-hexanol) sulfonate (di-TMHSS) and sodium bis (2-(pivaloyloxy)-ethanol) sulfonate (di-POESS) were synthesized to replace partial sodium bis (3,3,4,4,5,5,6,6,6-nonafluoro-hexanol) sulfonate (4FS(EO)2) to stabilize W/C microemulsions to decrease the fluorine content. The results showed that the stabilization abilit...
Source: The Journal of Supercritical Fluids - March 8, 2019 Category: Chemistry Source Type: research

Solubility of β-carotene and co-solutes in supercritical carbon dioxide for ternary systems: Experimental data and correlation
Publication date: Available online 6 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Abel Zúñiga-Moreno, Miguel G. Arenas-Quevedo, Octavio Elizalde-SolisAbstractTernary carbon dioxide – β-carotene – co-solute systems have been studied with the aim of examining the equilibrium solubility of β-carotene and co-solutes in carbon dioxide at supercritical conditions. Co-solutes were α-tocopherol, palmitic acid, and capsaicin. Experiments were performed by using a semi-continuous type apparatus from 10 to 36 MPa at 308.15 and 328.15 K. Binary β-carotene ...
Source: The Journal of Supercritical Fluids - March 8, 2019 Category: Chemistry Source Type: research

Uniform and ultrathin carbon-layer coated layered Na2Ti3O7 and tunnel Na2Ti6O13 hybrid with enhanced electrochemical performance for anodes in sodium ion batteries
Publication date: Available online 6 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Jieun Hwang, Handi Setiadi Cahyadi, Wonyoung Chang, Jaehoon KimAbstractUltrathin and uniform carbon layer-coated layered Na2Ti3O7 and tunnel Na2Ti6O13 hybrids were synthesized via a facile and fast method using supercritical methanol and subsequent carbon coating with liquid carbon dioxide as a coating solvent. The carbon content and relative composition of the layered Na2Ti3O7 and tunnel Na2Ti6O13 phases in the hybrids were controlled by adjusting the calcination temperature. The drawbacks of each material could be overcom...
Source: The Journal of Supercritical Fluids - March 8, 2019 Category: Chemistry Source Type: research

Equation of State and Thermodynamic Properties for Mixtures of H2O, O2, N2, and CO2 from Ambient up to 1000 K and 280 MPa
Publication date: Available online 5 March 2019Source: The Journal of Supercritical FluidsAuthor(s): F. Mangold, St. Pilz, S. Bjelic, F. VogelAbstractSupercritical water oxidation (SCWO) is an effective technique to treat wet organic wastes. Its modeling requires an accurate calculation of thermodynamic properties. In this work an equation of state (EOS) is proposed which accurately predicts the thermodynamic state of mixtures of water, oxygen, nitrogen, and carbon dioxide for a wide range of compositions, temperatures, and pressures including supercritical conditions. The EOS includes a volume translation, an evolved &alp...
Source: The Journal of Supercritical Fluids - March 6, 2019 Category: Chemistry Source Type: research

Studies on the thermal-hydraulic performance of zigzag channel with supercritical pressure CO2
Publication date: Available online 4 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Haiyan Zhang, Jiangfeng Guo, Xiulan Huai, Keyong Cheng, Xinying CuiAbstractThe numerical investigations of zigzag channel showed that the reduction of the zigzag bend angle improves heat transfer performance but worsens hydraulic performance. The heat transfer enhancement has much to do with the decrease of the entropy generation and the increase of the synergy between the velocity and the temperature gradient. The larger heat effectiveness corresponds to better convective heat transfer effectiveness, and a very small heat ...
Source: The Journal of Supercritical Fluids - March 6, 2019 Category: Chemistry Source Type: research

Physiological Activities and Bioactive Compound from Laver (Pyropia yezoensis) Hydrolysates by Using Subcritical Water Hydrolysis
This study aimed to create P. yezoensis hydrolysates, via subcritical water hydrolysis (SWH), which can enhance food functionality. P. yezoensis hydrolysates were produced at (120 to 230) °C and 30 bar. Extraction was performed using hot water and ethanol for comparison. The maximum radical-scavenging activity of DPPH and ABTS was (16.63 ± 0.20) mg trolox/g dried mass and (19.45 ± 0.07) mg trolox/g dried mass, respectively. The total phenolic, protein, and reducing sugar content was (14.29 ± 0.33) mg gallic acid/g dried mass, (20.21 ±&t...
Source: The Journal of Supercritical Fluids - March 6, 2019 Category: Chemistry Source Type: research

Transformation of lignin under uniform heating. I. Gasification in a flow of water vapor and supercritical water
Publication date: Available online 2 March 2019Source: The Journal of Supercritical FluidsAuthor(s): Oxana N. Fedyaeva, Anatoly A. Vostrikov, Andrey V. Shishkin, Mikhail Ya. SokolAbstractThe paper presents the research results on the lignin gasification in a flow of water vapor and supercritical water (SCW) at uniform heating (1.5 K/min) of the tubular reactor to 928 K. It was revealed that the highest yield of thiols and H2S occurs at T 748 K. The maximum yield of phenols is observed at 658 − 703 K. It is shown that in consequence of SCW gasification of lignin, a carbonized ...
Source: The Journal of Supercritical Fluids - March 4, 2019 Category: Chemistry Source Type: research

Heat Treatment Induced Phase Transformations in Zirconia and Yttria-Stabilized Zirconia Monolithic Aerogels
Publication date: Available online 27 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Jorge Torres-Rodríguez, József Kalmár, Melita Menelaou, Ladislav Čelko, Karel Dvořak, Jaroslav Cihlář, Jaroslav Cihlař, Jozef Kaiser, Enikő Győri, Péter Veres, István Fábián, István LázárAbstractMonolithic, structurally stable zirconia (ZrO2) aerogels can be used in high temperature applications and as medical implants. The macroscopic properties of these solids can be fine-tuned by the appropriate thermal treatment of the amorphous aerog...
Source: The Journal of Supercritical Fluids - February 28, 2019 Category: Chemistry Source Type: research

Fume silica improves the insulating and mechanical performance of silica aerogel/glass fiber composite
Publication date: Available online 27 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Sameera Shafi, Jiaqi Tian, Rahul Navik, Yanzhe Gai, Xiao Ding, Yaping ZhaoAbstractIn this work, we prepared the mechanically strong and highly insulated composite of the silica aerogel/glass fiber by adding fumed silica. The composite was made by acid-base catalyzed tetraethyl orthosilicate sol-gel, to which the fumed silica was added, followed by supercritical CO2 drying technique. The resultant composite possesses not only ultra-low thermal conductivity of 0.0194 W·(m·K)−1 but also excellent...
Source: The Journal of Supercritical Fluids - February 28, 2019 Category: Chemistry Source Type: research

3D Aerogel of Cellulose Triacetate with Supercritical Antisolvent Process for Drug Delivery
Publication date: Available online 27 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Wang Cheng, Satoko OkubayashiAbstractA novel biocompatible and hydrophobic drug-loaded cellulose triacetate (CTA) aerogel was prepared using supercritical antisolvent process for drug delivery system. In this work, it was investigated the influences of the size and the distribution of drug in the CTA aerogels on the drug release property. All CTA aerogels showed high loading capacity with 3D irregularly shaped nanoscale pores. The CTA/paracetamol (PA) aerogels had low volume shrinkage and high drug content from 19.8% to...
Source: The Journal of Supercritical Fluids - February 28, 2019 Category: Chemistry Source Type: research

Supercritical CO2 Extraction and Selective Adsorption of Aroma Materials of Selected Spice Plants in Functionalized Silica Aerogels
Publication date: Available online 27 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Enikő Győri, Anita Varga, István Fábián, István LázárAbstractStatic supercritical fluid extraction has been used to concentrate the aroma materials of common herbs and spices. The technique has provided a higher number of components and cleaner extract than the one-step ethanol maceration. The one-step supercritical fluid extraction of the aroma compounds has been combined with their in situ adsorption in hydrophilic and hydrophobic silica aerogels. The extracts have been anal...
Source: The Journal of Supercritical Fluids - February 27, 2019 Category: Chemistry Source Type: research

Stability and activity maintenance of sol-gel Ni-MxOy (M=Ti, Zr, Ta) catalysts during continuous gasification of glycerol in supercritical water
Publication date: Available online 27 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Sha Li, Phillip E. Savage, Liejin GuoAbstractThe long-term stability of activities and physicochemical properties for nickel nanoparticles supported on TiO2, ZrO2 and Ta2O5 prepared by sol-gel methods, was evaluated for continuous supercritical water gasification (SCWG) of 3 wt.% glycerol at 425 °C and 25.2 MPa. The Ni/TiO2 catalyst bed gradually deactivated while the Ni/ZrO2 and Ni/Ta2O5 catalyst beds showed persistent and high carbon gasification efficiency for 80 h operation. Character...
Source: The Journal of Supercritical Fluids - February 27, 2019 Category: Chemistry Source Type: research

Flow and heat transfer of supercritical CO2 in the honeycomb ultra-compact plate heat exchanger
Publication date: Available online 25 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Binbin Pei, Zhentao Chen, Fangbo Li, Bofeng BaiAbstractThe honeycomb Ultra-compact Plate Heat Exchanger (UCPHE) with hexagonal channels is proposed to be the recuperator in the supercritical CO2 (SCO2) Brayton cycle. The flow and heat transfer characteristics of the SCO2 in the UCPHE are investigated numerically by means of SST k-ω turbulence model. The study shows that the buoyancy effect has weak effect on heat transfer due to the insignificant variation in the thermo-physical properties of the SCO2 under the hi...
Source: The Journal of Supercritical Fluids - February 26, 2019 Category: Chemistry Source Type: research

Supercritical carbon dioxide as an effective medium for poly(naphthoylenebenzimidazole)’s synthesis
Publication date: Available online 22 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Nataliya M. Belomoina, Еlena G. Bulycheva, Igor V. Elmanovich, Mikhail I. Buzin, Rоman S. Begunov, Ivan S. Chashchin, Lyubov A. WassermanAbstractA study of formation of poly(naphthoylenebenzimidazole)’s in supercritical CO2 in the absence of any hazardous solvents was performed. Polycondensation reaction was performed in supercritical CO2 at a temperature of 90 °C and a pressure of 15 MPa for 8 hours in the presence of a catalyst – a mixture of benzoic acid and benzimidazole. A num...
Source: The Journal of Supercritical Fluids - February 23, 2019 Category: Chemistry Source Type: research

Organically-modified silica aerogels: a density functional theory study
Publication date: Available online 23 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Pedro Maximiano, Luísa Durães, Pedro SimõesAbstractThe primary particles of silica aerogels resulting from three different mixtures of precursors – 50% tetramethylorthosilicate (TMOS)/50% vinyltrimethoxysilane (VMTS); 50% tetraethylorthosilicate (TEOS)/50% aminopropyltriethoxysilane and 50% TEOS/50% glycidylpropoxi – as well as aerogels of pure TMOS and VTMS, have been studied by quantum mechanics density functional theory calculations (DFT), at the B3LYP/6-311+G(d,p) level of theory). T...
Source: The Journal of Supercritical Fluids - February 23, 2019 Category: Chemistry Source Type: research

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Publication date: April 2019Source: The Journal of Supercritical Fluids, Volume 146Author(s): (Source: The Journal of Supercritical Fluids)
Source: The Journal of Supercritical Fluids - February 23, 2019 Category: Chemistry Source Type: research

Transformation of lignin under uniform heating. II. Combustion in a flow of water-oxygen mixture
Publication date: Available online 21 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Oxana N. Fedyaeva, Anatoly A. Vostrikov, Andrey V. Shishkin, Mikhail Ya. SokolAbstractThe research results on the lignin oxidation in a flow of water-oxygen mixture at uniform heating (1.5 K/min) of the tubular reactor to 733 K are presented. The temperature dependences of the products yield and composition are obtained. It is shown that 90.3% of carbon is removed from lignin as part of CO2 and CO. The maximum yield of phenols was detected at T
Source: The Journal of Supercritical Fluids - February 22, 2019 Category: Chemistry Source Type: research

Poly(Urethane-Acrylate) Aerogels from the Isocyanurate Trimer of Isophorone Diisocyanate
Publication date: Available online 21 February 2019Source: The Journal of Supercritical FluidsAuthor(s): Maria Papastergiou, Despoina Chriti, Dimitrios E. Damalas, Grigorios Raptopoulos, Patrina ParaskevopoulouAbstractPoly(urethane acrylate) aerogels were synthesized from radical polymerization of a dendritic monomer having an isocyanurate-based rigid/aliphatic core, urethane linkages and nine terminal acrylate groups. The rigidity of the core comes from the triisocyanate, an isophorone diisocyanate trimer (IPDI). The material properties of those aerogels were compared to the properties of related literature materials deri...
Source: The Journal of Supercritical Fluids - February 22, 2019 Category: Chemistry Source Type: research