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Research paper thumbnail of Extraction of Astaxantine and Phycocyanine from Microalgae with Supercritical Carbon Dioxide

Journal of Chemical and Engineering Data, 2003

Astaxantine from the microalga Haematococcus pluvialis and phycocyanine from the microalga Spirul... more Astaxantine from the microalga Haematococcus pluvialis and phycocyanine from the microalga Spirulina maxima have been obtained by supercritical extraction using carbon dioxide. Prior to extraction, the samples of microalgae were crushed by cutting mills (coffee mill) and then manually ground with dry ice (solid carbon dioxide). The Haematococcus extracts were analyzed by liquid chromatography, using astaxantin (purity of 98%) as

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Research paper thumbnail of On the choice of a third (and fourth) generalizing parameter for equations of state

Chemical Engineering Science, 1987

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Research paper thumbnail of A generalized Patel-Teja equation of state for polar and nonpolar fluids and their mixtures

Journal of Chemical Engineering of Japan, 1990

... 8. Equilibrium ratios at three temperatures for H2S and nonane using the generalized Patel-Te... more ... 8. Equilibrium ratios at three temperatures for H2S and nonane using the generalized Patel-Teja equation of state. ... King Fahd University of Petroleum & Minerals for its support, Mr. Ahmed A. Ibrahim for performing some of the calculations, and Mr. Tasudduq Husain K. Rahman ...

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Research paper thumbnail of Modified Soave-Redlich-Kwong equations of state applied to mixtures containing supercritical carbon dioxide

Korean Journal of Chemical Engineering, 2003

The well-known equation of state Soave-Redlich-Kwong and two of its modifications are applied to ... more The well-known equation of state Soave-Redlich-Kwong and two of its modifications are applied to describe vapor-liquid equilibrium in binary asymmetric mixtures, which contain supercritical carbon dioxide and a heavy component. Several mixing rules including the classical van der Waals mixing rules with one and two interaction parameters, non-quadratic mixing rules, and the used of a Gibbs free energy model, are used with these equations. Seven mixtures containing supercritical carbon dioxide are considered in the study. The experimental data were obtained from literature sources and the adjustable parameters were found by minimizing the errors between predicted and experimental data of the concentration of the solute in the liquid phase. The work allows concluding on the advantages, disadvantages and expected accuracy of these equations of state and mixing rules for correlating vaporliquid equilibrium data in asymmetric systems as those studied.

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Research paper thumbnail of Extraction of Astaxantine and Phycocyanine from Microalgae with Supercritical Carbon Dioxide

Journal of Chemical and Engineering Data, 2003

Astaxantine from the microalga Haematococcus pluvialis and phycocyanine from the microalga Spirul... more Astaxantine from the microalga Haematococcus pluvialis and phycocyanine from the microalga Spirulina maxima have been obtained by supercritical extraction using carbon dioxide. Prior to extraction, the samples of microalgae were crushed by cutting mills (coffee mill) and then manually ground with dry ice (solid carbon dioxide). The Haematococcus extracts were analyzed by liquid chromatography, using astaxantin (purity of 98%) as

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Research paper thumbnail of On the choice of a third (and fourth) generalizing parameter for equations of state

Chemical Engineering Science, 1987

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Research paper thumbnail of A generalized Patel-Teja equation of state for polar and nonpolar fluids and their mixtures

Journal of Chemical Engineering of Japan, 1990

... 8. Equilibrium ratios at three temperatures for H2S and nonane using the generalized Patel-Te... more ... 8. Equilibrium ratios at three temperatures for H2S and nonane using the generalized Patel-Teja equation of state. ... King Fahd University of Petroleum & Minerals for its support, Mr. Ahmed A. Ibrahim for performing some of the calculations, and Mr. Tasudduq Husain K. Rahman ...

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Research paper thumbnail of Modified Soave-Redlich-Kwong equations of state applied to mixtures containing supercritical carbon dioxide

Korean Journal of Chemical Engineering, 2003

The well-known equation of state Soave-Redlich-Kwong and two of its modifications are applied to ... more The well-known equation of state Soave-Redlich-Kwong and two of its modifications are applied to describe vapor-liquid equilibrium in binary asymmetric mixtures, which contain supercritical carbon dioxide and a heavy component. Several mixing rules including the classical van der Waals mixing rules with one and two interaction parameters, non-quadratic mixing rules, and the used of a Gibbs free energy model, are used with these equations. Seven mixtures containing supercritical carbon dioxide are considered in the study. The experimental data were obtained from literature sources and the adjustable parameters were found by minimizing the errors between predicted and experimental data of the concentration of the solute in the liquid phase. The work allows concluding on the advantages, disadvantages and expected accuracy of these equations of state and mixing rules for correlating vaporliquid equilibrium data in asymmetric systems as those studied.

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