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Zhen Huang - One of the best experts on this subject based on the ideXlab platform.
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Mass Transfer Models for Supercritical Fluid Extraction
Food Engineering Series, 2014Co-Authors: Zhen HuangAbstract:Extraction of bioactive species from various plant matrices by means of Supercritical Fluids has been widely investigated during the last few decades. In this chapter, recent advances of mass transfer models for representing kinetics of Supercritical Fluid Extraction processes have been summarized. The mass transfer models reviewed here include the most successful broken and intact cell model, the shrinking core model, the microstructured mathematical model, the heat analogue diffusion model and other relatively simple models. Supercritical Fluid Extraction of botanical matters may be influenced by the solute solubility limitation, solute–solid interactions, solid phase mass transfer coefficient and Fluid phase mass transfer coefficient, along with axial dispersion coefficient. Due to the limitations arising from complicated microstructures of plant matrices, sample pretreatments and optimization methods, further attempts are still requiring for developing theoretical mass transfer models for scaling-up and commercialization design of kinetic Supercritical Fluid Extraction processes.
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Theoretical models for Supercritical Fluid Extraction
Journal of Chromatography A, 2012Co-Authors: Zhen Huang, Xiao-han Shi, Wei-juan JiangAbstract:For the proper design of Supercritical Fluid Extraction processes, it is essential to have a sound knowledge of the mass transfer mechanism of the Extraction process and the appropriate mathematical representation. In this paper, the advances and applications of kinetic models for describing Supercritical Fluid Extraction from various solid matrices have been presented. The theoretical models overviewed here include the hot ball diffusion, broken and intact cell, shrinking core and some relatively simple models. Mathematical representations of these models have been in detail interpreted as well as their assumptions, parameter identifications and application examples. Extraction process of the analyte solute from the solid matrix by means of Supercritical Fluid includes the dissolution of the analyte from the solid, the analyte diffusion in the matrix and its transport to the bulk Supercritical Fluid. Mechanisms involved in a mass transfer model are discussed in terms of external mass transfer resistance, internal mass transfer resistance, solute-solid interactions and axial dispersion. The correlations of the external mass transfer coefficient and axial dispersion coefficient with certain dimensionless numbers are also discussed. Among these models, the broken and intact cell model seems to be the most relevant mathematical model as it is able to provide realistic description of the plant material structure for better understanding the mass-transfer kinetics and thus it has been widely employed for modeling Supercritical Fluid Extraction of natural matters.
Alejandro Cifuentes - One of the best experts on this subject based on the ideXlab platform.
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recent applications of on line Supercritical Fluid Extraction coupled to advanced analytical techniques for compounds Extraction and identification
IEEE Journal of Solid-state Circuits, 2019Co-Authors: A P Sanchezcamargo, Elena Ibanez, Fabian Paradaalonso, Alejandro CifuentesAbstract:In a previous review (Sanchez-Camargo et al., J. Sep. Sci. 40 (2017) 213-227), we discussed the application of on-line Supercritical Fluid Extraction coupled to chromatographic techniques. This review includes an update of the most recent publications (from January 2016 till June 2018) on this topic, which employs advanced analytical techniques for extracting and identifying valuable analytes. Supercritical Fluid Extraction has been widely recognized as a green sample preparation technique, because it is efficient, environmentally friendly, powerful, and faster, offering the possibility of direct coupling to analytical instrumental techniques. Among those techniques, Supercritical Fluid chromatography has experienced an innovative progression in the last 10 years, and the most recent applications of Supercritical Fluid Extraction are coupled to this advanced analytical tool. The general principles, both methodological and instrumental of on-line Supercritical Fluid Extraction coupled to Supercritical Fluid chromatography are described here. Besides, applications of the mentioned coupling for analysing biological Fluids, food, soil, and botanical samples are also presented and discussed. Finally, a brief description about the very recent on-line coupling of Supercritical Fluid Extraction to ion mobility spectrometry is presented, as well as concluding remarks about the importance of using these coupled techniques in the near future.
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On‐line coupling of Supercritical Fluid Extraction and chromatographic techniques
Journal of Separation Science, 2016Co-Authors: Andrea Del Pilar Sánchez-camargo, Fabián Parada-alfonso, Elena Ibanez, Alejandro CifuentesAbstract:This review summarizes and discusses recent advances and applications of on-line Supercritical Fluid Extraction coupled to liquid chromatography, gas chromatography and Supercritical Fluid chromatographic techniques. Supercritical Fluids, due to their exceptional physical properties, provide unique opportunities not only during the Extraction step but also in the separation process. Although Supercritical Fluid Extraction is especially suitable for recovery of non-polar organic compounds, this technique can also be successfully applied to the Extraction of polar analytes by the aid of modifiers. Supercritical Fluid Extraction process can be performed following “off-line” or “on-line” approaches and their main features are contrasted herein. Besides, the parameters affecting the Supercritical Fluid Extraction process are explained and a “decision tree” is for the first time presented in this review work as a guide tool for method development. The general principles (instrumental and methodological) of the different on-line couplings of Supercritical Fluid Extraction with chromatographic techniques are described. Advantages and shortcomings of Supercritical Fluid Extraction as hyphenated technique are discussed. Besides, an update of the most recent applications (from 2005 up to now) of the mentioned couplings is also presented in this review. This article is protected by copyright. All rights reserved
Shi Bing - One of the best experts on this subject based on the ideXlab platform.
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Mass transfer performance of Supercritical Fluid Extraction columns
Journal of Beijing University of Chemical Technology, 2001Co-Authors: Shi BingAbstract:A new model for describing mass transfer performance in the Supercritical Fluid Extraction columns by continuous counter current flow was derived. The model was tested by the experimented data in a Supercritical Fluid Extraction packed column, sieve tray column and spray column of 25mm in diameter respectively for the systems of Supercritical carbon dioxide isopropanol water and Supercritical carbon dioxide ethanol water by continuous counter current flow. It showed that the results predicted by the model agreed well with the experimental data.
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Study on hydrodynamics characteristics in Supercritical Fluid Extraction column
Journal of Beijing University of Chemical Technology, 2000Co-Authors: Shi BingAbstract:A new model for describing two phase flow in a Supercritical Fluid Extraction column was derived. The model was tested by two phase flow experiments carried out in packed column, spray column and sieve column all with 25 mm in diameter, respectively, with two Supercritical Fluid Extraction systems, which are carbon dioxide isopropanol water and carbon dioxide ethanol water by means of anti continuous current. It showed that the results of the model agreed well with the experimental data for predicting hydrodynamic performance.
Xu Song-lin - One of the best experts on this subject based on the ideXlab platform.
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Review of Mass Transfer Models in Supercritical Fluid Extraction of Botanical Essential Oil
Chemical Industry and Engineering, 2005Co-Authors: Xu Song-linAbstract:The Supercritical Fluid Extraction of botanical essential oil,a great application of Supercritical Extraction technique,has been widely studied in recent years.Some literatures have been reported on Supercritical Fluid Extraction of essential oil,but only few focuse on mass transfer in these Extraction processes.This paper reviews the mass transfer in Supercritical Fluid Extraction of essential oil in recent years.Three main mass transfer models and the trend in studying mass transfer have also been discussed.
Shi Bingjie - One of the best experts on this subject based on the ideXlab platform.
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Hydrodynamics and Mass Transfer Performance in Supercritical Fluid Extraction Columns
2002Co-Authors: Shi BingjieAbstract:New models for describing hydrodynamics and mass transfer performance in Supercritical Fluid Extraction columns were proposed. Those models were proved by experimental data, which were obtained in Supercritical Fluid Extraction packed column, spray column and sieve tray column respectively. The inner diameter of those columns areФ25 mm. These experimental systems include Supercritical carbon diox-ide-isopropanol-water and Supercritical carbon dioxide-ethanol-water, in which Supercritical carbon dioxide was dispersed phase, and another was continuous phase. The Extraction processes were operated with continuous countercurrent flow. The predicted values are agreed well with experimental data.