33. A. Rajendran, T. Gilkison, M. Mazzotti. Pressure drop effects in supercritical fluid chromatography, 1st International Conference on Supercritical Fluid Chromatography, Pittsburgh USA, Sept 2007 34. W. Chen, A. Rajendran. Optimization of binary separations in supercritical fluid chromatography, 1st International Conference on Supercritical Fluid Chromatography, Pittsburgh USA, Sept 2007 35. W. Chen, M. Aman Ullah, A. Rajendran. Chiral separation of flurbiprofen by supercritical fluid chro- matography, 1st International Conference on Supercritical Fluid Chromatography, Pittsburgh USA, Sept2007 36. A. Rajendran, S. Farooq, V. Kariwala. Blank correction in dynamic column breakthrough experiments, 9th International Conference on Fundamentals Of Adsorption, Sicily Italy, May 2007 37. A. Rajendran, T. Gilkison, M. Mazzotti. Pressure drop effects in supercritical fluid chromatography, 9th International Conference on Fundamentals Of Adsorption, Sicily Italy, May 2007 38. W. Chen, A. Rajendran. ...
[98 Pages Report] Check for Discount on United States Supercritical Fluid Chromatography (Sfc) Market Report 2017 report by QYResearch Group. In this report, the United States Supercritical Fluid Chromatography (Sfc)...
TY - JOUR. T1 - Supercritical fluid chromatography reduction of hydrogen/deuterium back exchange in solution-phase hydrogen/deuterium exchange with mass spectrometric analysis. AU - Emmett, Mark. AU - Kazazic, Sasa. AU - Marshall, Alan G.. AU - Chen, Wei. AU - Shi, Stone D H. AU - Bolaños, Ben. AU - Greig, Michael J.. PY - 2006/10/1. Y1 - 2006/10/1. N2 - The single biggest problem with solution-phase H/D exchange as a mass spectrometric probe of surface exposure in a protein (or protein complex) is back-exchange of H for D after the initial H/D exchange has been quenched. Back-exchange results in loss of pertinent data and also greatly hampers data analysis. Previously, very fast, cold (0-4 °C) HPLC was performed to help reduce back-exchange, but calculated back-exchange still averages ∼30%. In this report, supercritical fluid chromatography replaces HPLC as the desalting/separation technique prior to mass analysis, providing a dramatic reduction in back-exchange compared to the fast, cold ...
Palm oil is known to host a variety of phytonutrients; some having antioxidant property such as the carotenes and vitamin E. These antioxidants are also present in the oil recovered from the palm-pressed fibre. Study was carried out to investigate the presence of coenzyme Q10, yet another non-glyceride compound which possesses antioxidant property in crude palm oil (CPO) and palm fibre oil. Separation of coenzyme Q10 in CPO and palm fibre oil was carried out using supercritical fluid chromatography with ultra violet detection. 1H and 13C NMR were used for its characterisation. Calibration with authentic standard shows that there are 10-80 ppm coenzyme Q10 in CPO while its concentration in palm fibre oil is 1000-1500 ppm.
While supercritical fluid chromatography (SFC) has been available for decades, very few labs have chosen to take advantage of its remarkable chromatographic properties. The separation of isomeric compounds that are usually challenging for high.performance liquid chromatography (HPLC) can be accomplished by SFC. Coupling the exceptional chromatographic properties of SFC with the sensitivity of mass spectrometric detection results in a powerful piece of equipment that very few laboratories have utilized. Glycosphingolipids (GSLs) are characteristic components of eukaryotic cells, found in the carbohydrate-rich cell membrane. They represent hundreds of diverse chemical structures composed of different carbohydrate and ceramide moieties. The simplest hexosylceramides (HexCer), which are neutral GSLs, are represented by glucosylceramide (GluCer) and galactosylceramide (GalCer). GluCer and GalCer undergo their own distinctive metabolic pathways that effect different biological responses. GSL ...
Preparative Supercritical Fluid Chromatography (pSFC). As an environment-friendly approach to purification applications, pSFC is being used routinely for an increasing number of applications.. During the recent years SFC has gained acceptance in drug discovery for high-throughput purification of enantiomers. Hence, pSFC replaces preparative HPLC (pHPLC) as major technology for chiral separations in many pharmaceutical companies. Preparative SFC excels not only at separating and purifying chiral compounds but is also powerful for achiral separations and can be implemented in most steps of drug discovery. It may offer potential advantages over pHPLC for purity upgrading of active pharmaceutical ingredients or drug intermediates, impurity isolation and non-aqueous purification.. The use of pSFC as an alternative option to pHPLC receives also a growing interest for natural products, environmental (pesticides) and petroleum (biofuels) applications. ...
Preparative Supercritical Fluid Chromatography (pSFC). As an environment-friendly approach to purification applications, pSFC is being used routinely for an increasing number of applications.. During the recent years SFC has gained acceptance in drug discovery for high-throughput purification of enantiomers. Hence, pSFC replaces preparative HPLC (pHPLC) as major technology for chiral separations in many pharmaceutical companies. Preparative SFC excels not only at separating and purifying chiral compounds but is also powerful for achiral separations and can be implemented in most steps of drug discovery. It may offer potential advantages over pHPLC for purity upgrading of active pharmaceutical ingredients or drug intermediates, impurity isolation and non-aqueous purification.. The use of pSFC as an alternative option to pHPLC receives also a growing interest for natural products, environmental (pesticides) and petroleum (biofuels) applications. ...
The effect of pressure drop on the performance of supercritical fluid chromatography systems using a modified mobile phase (carbon dioxide + ethanol) was studied. Experiments were performed on a Lichrospher-RP-18 column with phenanthrene as a solute. A wide range of back pressures (130 to 210 bar) and modifier concentrations (2 to 7% w/w) have been explored. Experiments yielding both small and large pressure drops were performed. From these experiments, parameters to describe pressure drop, retention, and column efficiency were extracted, and were used to simulate the dynamics of the chromatographic column. A good match between the experimentally measured and calculated values of pressure drop, retention times, and column efficiency was observed. At low back pressure and modifier composition, significant loss of column efficiency was observed.
François, I., Dos Santos Pereira, A., & Sandra, P. (2009). Comprehensive and off-line supercritical fluid chromatography: reversed phase liquid chromatography for the analysis of complex triglyceride profiles. High Performance Liquid Phase Separations and Related Techniques, 34th International symposium, Abstracts. Presented at the 34th International symposium on High Performance Liquid Phase Separations and Related Techniques (HPLC 2009 ...
WORCESTER, Mass., July 12, 2013 /PRNewswire/ -- Averica Discovery Announces Winner of First Averica Award for Supercritical Fluid Chromatography (SFC). -...
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(PRWEB) September 10, 2014 -- The European Supercritical fluid chromatography reagents report defines and segments the concerned market in Europe with analysis
Mass spectrometry (MS) is a technique widely implemented for the measurement of environmental pollutants. A critical tool for the analysis of persistent organic pollutants (POPs) over several decades, MS as coupled with liquid and gas chromatography (LC and GC) techniques enables the analysis of emerging POPs. The aim of this thesis was to investigate the use of alternative MS-based techniques to assist specific analytical challenges including separation of stereoisomers using supercritical fluid chromatography (SFC), reduced ionization competition with appropriate mobile phase additives, and applied rotationally averaged collision-cross section (CCS) of ions via ion mobility measurements of emerging POPs.. Chromatographic efficiency improvements for the brominated flame retardant, hexabromocyclododecane (HBCDD), were implemented through the development of two supercritical fluid chromatography (SFC) methods. Based on the inherent qualities of supercritical fluids, separation of both predominant ...
Mass spectrometry (MS) is a technique widely implemented for the measurement of environmental pollutants. A critical tool for the analysis of persistent organic pollutants (POPs) over several decades, MS as coupled with liquid and gas chromatography (LC and GC) techniques enables the analysis of emerging POPs. The aim of this thesis was to investigate the use of alternative MS-based techniques to assist specific analytical challenges including separation of stereoisomers using supercritical fluid chromatography (SFC), reduced ionization competition with appropriate mobile phase additives, and applied rotationally averaged collision-cross section (CCS) of ions via ion mobility measurements of emerging POPs.. Chromatographic efficiency improvements for the brominated flame retardant, hexabromocyclododecane (HBCDD), were implemented through the development of two supercritical fluid chromatography (SFC) methods. Based on the inherent qualities of supercritical fluids, separation of both predominant ...
TY - JOUR. T1 - Highly porous organic nanoparticles formed from supercritical carbon dioxide mediated sol-emulsion-gel method. AU - Lee, Jun Young. AU - Kim, Jung Hyun. PY - 2004/5/5. Y1 - 2004/5/5. N2 - Highly porous organic nanoparticles have been prepared by adapting a novel method, sol-emulsion-gel process, through stable dispersion of nanometer-scaled emulsion droplets into continuous phase of supercritical carbon dioxide (ScCO2), sol-gel chemistry in emulsion droplets, and then supercritical drying. This principle offers faithful preparation of nanoparticles (35-90 nm in diameter) having pores of 1-3 nm in radius and high specific surface area (over 2000 m2/g).. AB - Highly porous organic nanoparticles have been prepared by adapting a novel method, sol-emulsion-gel process, through stable dispersion of nanometer-scaled emulsion droplets into continuous phase of supercritical carbon dioxide (ScCO2), sol-gel chemistry in emulsion droplets, and then supercritical drying. This principle offers ...
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A specialty phase designed for SFC with a high density Diol surface coverage which ensures separations better and more reproducible than conventional unbonded silica. GreenSep Diol is particularly suitable for acidic and basic analytes.
The Laboratory for the Analysis of Medicines (LAM) has developed a solid expertise in drug analysis and bioanalysis. Its scope of interest has been extended to diagnostic biomarkers and biopharmaceuticals. Research and routine activities take place in a quality environment.
The piquant and peppery flavor of American Blue and Roquefort cheese is largely due to the short and medium chain fatty acids, methyl ketones and secondary alcohols. The free fatty acids contribute flavor themselves and are also precursors of methyl ketones. Lipase action during the cheese ripening leads to formation of free fatty acids (FFA). The short chain FFA (C6 to C10) are more peppery in flavor than long chain FFA. Conventional methods of FFA analysis suffer from limitations such as loss of volatile fatty acids during derivatization of samples and difficulties in extraction and separation of short, medium and long chain fatty acids in a single analysis. Enhanced FFA recoveries from spiked matrix samples were obtained at 680 atm by SFE/SFC procedure with a 5% methanol modifier containing 1% acetic acid. A procedure was developed utilizing supercritical fluid extraction to isolate the FFA and subsequently separate and quantitate the FFA with supercritical fluid chromatography. The ...
The solubility of heptanoic acid and octanoic acid in supercritical carbon dioxide has been determined at temperatures of (313.15, 323.15, and 333.15) K over a pressure range of (8.5 to 30.0) MPa, depending upon the solute. The solubility of heptanoic acid ranged from a solute concentration of (0.08 ± 0.03) kg • m -3 (T = 323.15 K, p = 8.5 MPa) to (147 ± 0.2) kg • m -3 (T = 323.15 K, p = 20.0 MPa). The lowest octanoic acid solubility obtained was a solute concentration of (0.40 ± 0.1) kg • m -3 (T = 333.15 K, p = 10.0 MPa), while the highest solute concentration was (151 ± 2) kg • m -3 (T = 333.15 K, p = 26.7 MPa). In addition, solubility experiments were performed for nonanoic acid in supercritical carbon dioxide at 323.15 K and pressures of (10.0 to 30.0) MPa to add to the solubility data previously published by the authors. In general, carboxylic acid solubility increased with increasing solvent density. The results also showed that the solubility of the solutes decreased with ...
TY - JOUR. T1 - Highly Fluorous Complexes of Ruthenium and Osmium and Their Solubility in Supercritical Carbon Dioxide. AU - Berven, Bradley. AU - Koutsantonis, George. AU - Skelton, Brian. AU - Trengove, R.D.. AU - White, Allan. PY - 2009. Y1 - 2009. N2 - A series of ruthenium and osmium complexes containing highly fluorous diphosphine ligands FPPF = (F13C6C6H4-p)2P(CH2)2P(p-C6H4C6F13)2 (dfppe) and (F13C6C6H4-p)2P(CH2)3P(p-C6H4C6F13)2 (dfppp) has been prepared. The fluorous diphosphine ligands incorporate four C6F13 "fluoro-ponytails", and these have been effective in solubilizing the complexes in supercritical carbon dioxide (scCO2). Precise solubility measurements in scCO2 were performed for some of the complexes. The new complexes [MX2(FPPF)2] and [MX(FPPF)(η-C5H5)], M = Ru, Os, X = Cl, Br, have been characterized by a number of spectroscopic techniques and their electrochemical properties measured, three of the ruthenium complexes also being characterized by single-crystal X-ray studies. ...
The effects of microwave irradiation (2.45 GHz, 200 W) on glycosylation promoted by a solid super acid in supercritical carbon dioxide was investigated with particular attention paid to the structure of the acceptor substrate. Because of the symmetrical structure and high diffusive property of supercritical carbon dioxide, microwave irradiation did not alter the temperature of the reaction solution, but enhanced reaction yield when aliphatic acceptors are employed. Interestingly, the use of a phenolic acceptor under the same reaction conditions did not show these promoting effects due to microwave irradiation. In the case of aliphatic diol acceptors, the yield seemed to be dependent on the symmetrical properties of the acceptors. The results suggest that microwave irradiation do not affect the reactivity of the donor nor promoter independently. We conclude that the effect of acceptor structure on glycosylation yield is due to electric delocalization of hydroxyl group and dielectrically symmetric
Effect of supercritical carbon dioxide on micro-mechanical properties of electrodesposited goldEffect of supercritical carbon dioxide on micro-mechanical properties of electrodesposited gold ...
In 1822, almost 200 years ago, Baron Charles Cagniard de Latour (1777-1859) discovered the critical phenomena or critical state [1] [2]. At that time, it was described as a curiosity. However, it is now used as an advanced extraction and analytical technology in industry and research. Extraction with supercritical fluids (SFs) was welcome from the very beginning. In the present paper, the application to chromatography of the critical phenomena of compressed gases or overheated liquids as supercritical fluids will be discussed. Supercritical Fluid Chromatography (SFC) received an uneasy welcome, mainly because of the lack of commercially available analytical instruments. Even today, only a small number of industrial companies are manufacturing SFC instrumentation. A very small spectrum of columns is manufactured specially for SFC. SFC is not accepted by Pharmacopeia committees for the analysis of drugs and medical forms to the same extent as Gas Chromatography, High-Performance Liquid Chromatography or
Alibaba.com offers 198 supercritical co2 fluid extraction device products. About 56% of these are other pharmaceutical machinery, 1% are oil pressers, and 1% are laser beauty equipment. A wide variety of supercritical co2 fluid extraction device options are available to you,
The presence of carbon dioxide in natural gas, synthetic gas and liquid streams has prompted the industrial community to examine the properties of carbon dioxide mixtures with the intent of finding novel methods for removing this acidic impurity. Carbon dioxide is also of interest to researchers because it possesses a readily accessible critical point. This has stimulated studies of the phase behaviour and thermodynamic properties of supercritical fluid mixtures, particularly in systems used in supercritical fluid chromatography (SFC) and supercritical fluid extraction (SFE). For both of these applications, it is important to obtain information pertaining to the vapour-liquid phase boundaries for the carbon dioxide mixtures and their thermodynamic properties over a wide range of pressure and temperature. The (CO: + MeOH) system is of interest to applied research on fluid properties because the pure liquids have widely differing critical points. -- There are many experimental issues associated ...
The aim of this work was to evaluate the potential of supercritical carbon dioxide (CO2) to extract Fatty Acid Methyl Esters (FAME) from the microalgae Nannochloropsis oculata (N. oculata) at low temperatures (37 and 55 oC) and pressures (5.9 and 7.6 megapascals (MPa)). A qualitative gas chromatography (GC) analysis showed that the individual FAMEs extracted varied depending on the co-solvent (methanol or hexane) used with supercritical CO2. Using hexane, FAME compounds produced were similar to those extracted with soxhlet extraction alone while longer chain FAME were produced when methanol was the co-solvent. The effects of pressure and temperature variations were shown to be of statistical significance. The chromatograms produced in this work demonstrate that altering one of these parameters (co-solvent, temperature, pressure) can produce different compounds owing to the tunability of the technique.
The effects of organic modifier and temperature on the enantioseparation of 10 triazoles and eight imidazoles, using supercritical fluid chromatography with the Chiralpak AD column, have been investigated in this work. For this purpose four different organic modifiers (methanol, ethanol, 2-propanol and acetonitrile) were evaluated. Only in the case of two compounds could the enantiomeric separation not be achieved with any of the modifiers tested; the rest of compounds were baseline or partially resolved with at least one of the modifiers. The alcohol-type modifiers provided the best results in terms of retention time and resolution. In general, retention increased in the order methanol | ethanol | 2-propanol; moreover it was possible to establish a relationship between the retention and the number of aromatic rings and dioxolane groups in the molecule, that is, the higher the number is, the higher the retention time. From the study of the temperature effect, the enthalpy-entropy compensation was
The first three chapters of the book discuss the various chromatographic and mass spectroscopic techniques now available. Chapters 3-8 cover the complementary methods, based on the combination of mass spectroscopy with various chromatographic techniques such as high-performance liquid chromatography, gas chromatography and supercritical fluid chromatography.
The first three chapters of the book discuss the various chromatographic and mass spectroscopic techniques now available. Chapters 3-8 cover the complementary methods, based on the combination of mass spectroscopy with various chromatographic techniques such as high-performance liquid chromatography, gas chromatography and supercritical fluid chromatography.
Combining state-of-the-art media manufacturing with the industry leading column technology, Viridis Supercritical Fluid Chromatography (SFC) columns bring a new level of reproducibility to the world of laboratory scale purification. Viridis SFC columns are available for analytical and preparative chromatography as Viridis SFC 2-Ethylpyridine columns and Viridis SFC Silica columns. Larger preparative column formats are manufactured using Waters patented Optimum Bed Density (OBD) Technology. 2-Ethylpyridine chemistry is successfully used for a wide range of achiral SFC applications due to its retention, peak shape and selectivity properties. Viridis SFC 2-ethylpyridine columns also provide high reliability and reproducibility and can be used for analytical and preparative applications. Based on Waters long history of chromatographic silica production, the Viridis SFC Silica columns are designed to be highly reproducible and predictable based on tight product specifications and very low metal content.
Supercritical fluid chromatography (SFC) is an orthogonal technique to UHPLC. In recent years, SFC has demonstrated potential for use in the analysis of a broad variety of analytes of different polarities, if modifiers and additives are utilized as additional mobile phase constituents. However, to date, little research has been carried out on ion-exchange separation of highly polar and ionic analytes using SFC. The objective of this work was to investigate the elution characteristics of polar compounds using SFC combined with tandem mass spectrometry. Highly polar and even ionic drugs and metabolites, with a diversity of functional groups such as gamma-hydroxybutyrate (GHB), gamma-butyrolactone, GHB-glucuronide, ethyl sulfate, ethyl glucuronide as well as meldonium and gamma-butyrobetaine, were selected for the study. To investigate the chromatographic behavior of the solutes using SFC, a systematic chromatographic method development workflow including a basic validation in human urine was ...
In this project the photodegradation of 3,5-diamino-6-chloro-N-(2-(methylamino)ethyl)pyrazine-2-carboxamide was studied. A hypothetical degradation pattern for the compound was proposed and the aim of the project was to study the formed secondary photodegradants and to, if possible, structure elucidate some of these compounds. In order to do this, the parent compound was photodegraded in two steps, where a primary photodegradant was isolated using semi-preparative supercritical fluid chromatography (SFC) and then further degraded into the secondary photodegradants.. The photodegradation was first carried out in aqueous solution, where the parent compound was irradiated in UV-A light of 300-400 nm. This resulted in a primary photodegradant with a molecular ion of m/z = 227, where the chloride in position 6 of the pyrazine group had been replaced by a hydroxyl group. During the large scale photodegradation, prior to the preparative purification, the yield of primary photodegradant was very low due ...
A review on the use of packed capillary columns in gas chromatography (GC) is presented. Several articles on the invention of packed capillary columns have been published, as well as on the progress and the development of this technology. Practical applications by this technique have also been studied, especially in the period from 1996 and onwards. A recently developed technique, solvating gas chromatography (SGC), which uses CO2 as the mobile phase combined with a high inlet pressure, has received specific focus.. The use of packed capillary columns in GC has also been evaluated. The technique used to pack these columns has been developed from a similar technology, which have been used for packing of columns, achieving very good separations, for both supercritical fluid chromatography (SFC) and high performance liquid chromatography (HPLC). In the present work, the possibilities of using packed capillary columns in GC, without applying a higher inlet pressure than 5 bar, has been explored. A ...
The goal of this PhD work is to evaluate the possibilities of supercritical fluid chromatography (SFC) in the pharmaceutical analysis. This chromatographic approach will be used to develop analytical methods for numerous types of drugs (including chiral ones) in pharmaceutical formulations. Some inventive strategies will be developed to maximize performance and apply SFC to the widest possible range of molecules. The performance of SFC will be systematically compared to liquid chromatography (LC). In parallel, the PhD candidate will also have the opportunity to couple SFC with single quadrupole(MS), triple quadrupole (MS/MS) and high resolution (QqTOF/MS) mass spectrometers available in our laboratory. This instrumental setup will be used for the determination of drugs and metabolites in complex matrixes, such as biological fluids.. ...
Detection of drugs at low concentration is required in a variety of biological and medical situations, in order to avoid harmful side effects posed by some drug residues. The book details the instrumentation, detection, and application of nano chromatography (that is, any chromatographic and capillary electrophoretic method dealing with the detection of a sample at nano gram per liter or lower) and capillary electrophoresis in the analyses of biological and environmental samples. Methods discussed include: Nano Gas Chromatography, Nano Capillary Electrophoresis, Nano Chiral Chromatography, Micellar Electrokinetic Chromatography, Supercritical Fluid Chromatography, and Nano High Performance Liquid Chromatography.. ...
D6550 Standard Test Method for Determination of Olefin Content of Gasolines by Supercritical-Fluid Chromatography D6591 Standard Test Method for Determination of Aromatic Hydrocarbon Types in Middle Distillates-High Performance Liquid Chromatography Method with Refractive Index Detection. D6750 Standard Test Methods for Evaluation of Engine Oils in a High-Speed, Single-Cylinder Diesel Engine-1K Procedure (0.4 % Fuel Sulfur) and 1N Procedure (0.04 % Fuel Sulfur). D6987/D6987M Standard Test Method for Evaluation of Diesel Engine Oils in T-10 Exhaust Gas Recirculation Diesel Engine. D7347 Standard Test Method for Determination of Olefin Content in Denatured Ethanol by Supercritical Fluid Chromatography. D7422 Standard Test Method for Evaluation of Diesel Engine Oils in T-12 Exhaust Gas Recirculation Diesel Engine. D7484 Standard Test Method for Evaluation of Automotive Engine Oils for Valve-Train Wear Performance in Cummins ISB Medium-Duty Diesel Engine. D7549 Standard Test Method for Evaluation of ...
This application brief successfully demonstrates to convert the compendial normal phase HPLC method for the assay of dapsone tablets to a supercritical fluid chromatography (SFC) method using the Waters ACQUITY UPC2 System.
Surpercritical CO2 reactor Surpercritical CO2 extractor Surpercritical CO2 phase monitor Investigator Supercritical fluid Chromatography System A series of high pressure reactors (Endeavour, HEL, Parr, Autoclave Engineers) REACT IR Several LC-MS Several GC-MS Several flash chromatography separation systems NMR facility Mass spectrometry facility Solvent purification systems
Two sparse Bayesian methods were used to derive predictive models of solubility of organic dyes and polycyclic aromatic compounds in supercritical carbon dioxide (scCO(2)), over a wide range of temperatures (285.9-423.2K) and pressures (60-1400 bar): a multiple linear regression employing an expectation maximization algorithm and a sparse prior (MLREM) method and a non-linear Bayesian Regularized Artificial Neural Network with a Laplacian Prior (BRANNLP). A randomly selected test set was used to estimate the predictive ability of the models. The MLREM method resulted in a model of similar predictivity to the less sparse MLR method, while the non-linear BRANNLP method created models of substantially better predictivity than either the MLREM or MLR based models. The BRANNLP method simultaneously generated context-relevant subsets of descriptors and a robust, non-linear quantitative structure-property relationship (QSPR) model for the compound solubility in scCO(2). The differences between linear ...
Phytantriol-based organogels as a new type of immobilisation matrix were tested for their potential application as solid-phase catalysts with both isooctane and supercritical carbon dioxide as external solvents. It was shown that Mucor miehei lipase immobilised in such organogels is capable of catalysing the esterification of 1-propanol and lauric acid in both solvents. In order to determine the operational stability of the immobilised lipase in phytantriol-based organogels, reuse experiments were conducted in isooctane. They showed that the catalytic activity is quite well preserved despite the fact that a loss of phytantriol occurs due to its extraction from the gel ...
The solubility of an anthraquinone dye, 1,4-bis-(n-propylamino)-9,10-anthraquinone in supercritical carbon dioxide have been correlated with two equation of state. All critical properties have been estimated with a group contribution method (GCM). As far we know, solubility data for this dye never has been correlated using an equation of state (EOS). Therefore, it is worthwhile to model the solubility of this dye. In this work, the aim is correlating reported data with a new EOS and comparing obtained results with the results of Peng-Robinson EOS (PR-EOS) together with two adjustable parameter van der Waals mixing and combining rules. The calculated results showed that new EOS is more accurate than PR-EOS ...
A series of ruthenium and osmium complexes containing highly fluorous diphosphine ligands FP∧PF = (F13C6C6H4-p)2P(CH2)2P(p-C6H4C6F13)2 (dfppe) and (F13C6C6H4-p)2P(CH2)3P(p-C6H4C6F13)2 (dfppp) has been prepared. The fluorous diphosphine ligands incorporate four C6F13 "fluoro-ponytails", and these have been effective in solubilizing the complexes in supercritical carbon dioxide (scCO2). Precise solubility measurements in scCO2 were performed for some of the complexes. The new complexes [MX2(FP∧PF)2] and [MX(FP∧PF)(η-C5H5)], M = Ru, Os, X = Cl, Br, have been characterized by a number of spectroscopic techniques and their electrochemical properties measured, three of the ruthenium complexes also being characterized by single-crystal X-ray studies. The noncovalent interactions observed in the X-ray structures have been analyzed by the Hirshfeld surface approach, putting them on a more solid footing. The fluorinated complexes show significantly different solvation properties from those of the ...
Supercritical Carbon Dioxide Brayton cycles can be used in conjunction with a host of heat sources associated with different magnitudes of net power generation. In this paper, the overall design features of the turbomachinery, namely the turbine and compressor are evaluated for kilowatt to Gigawatt range of net cycle power using a commercial design tool - AxSTREAM®. The thermodynamic cycle considered in all cases is a simple recuperated Brayton cycle with turbine and compressor inlet temperatures of 540 °C and 45 °C respectively. The highest and lowest pressures in the cycle are 210 bar and 85 bar respectively. The preliminary design is carried out using an inverse algorithm with a meanline solver that generates many geometries for the given boundary conditions using standard loss correlations to account for different losses in turbomachines. It, thus, provides the general design features of the compressor and turbine which include - machine size, shaft speed at design point, overall ...
The influence of amine oxide catalysis has been investigated in the dispersion polymerisation of 2,4-toluenediisocyanate with 1,4-butanediol in supercritical carbon dioxide. In reactions stabilised by a diisocyanate terminated polydimethylsiloxane (PDMS) macromonomer, the concentration of N-methylmorpholine N-oxide
Author: Pandey, S. et al.; Genre: Journal Article; Published in Print: 2002-02-21; Title: The photophysics of 6-(1-pyrenyl)hexyl-11(1-pyrenyl)undecanoate dissolved in organic liquids and supercritical carbon dioxide: Impact on olefin metathesis
The target of this project is the screening of the opportunities, resulting of the combination of treating Cellulosic bodies with supercritical carbon dioxide. In general, the change of the porous structure depending on the way of fiber drying and the opportunity to incorporate active compounds and the development of analytical methods to track them within Cellulosic bodies.
This Tutorial Review focuses on supercritical carbon dioxide (scCO2), and discusses some of the problems that have frustrated its wide use on an industrial scale. It gives some recent examples where strategies have been developed to reduce the energy requirements, including sequential reactions and gas-expan Green Chemistry
Fingerprint Dive into the research topics of Mass transfer studies on the dehydration of supercritical carbon dioxide using dense polymeric membranes. Together they form a unique fingerprint. ...