New method for measuring obstructive factors and porosity using gas chromatographic instrumentation

Fundamental Relationships of Chromatography

“…The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67]. The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67].…”

“…For gas chromatography a velocity of about 2 ■*opt i called the practical operating gas velocity, is frequently recommended [67]. Provided that the ascending portion of the van Deemter curve is fairly flat at higher velocities than u opt , then the loss in efficiency will be small and well worth the saving in separation time.…”

Fundamental Relationships of Chromatography

“…The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67]. The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67].…”

“…For gas chromatography a velocity of about 2 ■*opt i called the practical operating gas velocity, is frequently recommended [67]. Provided that the ascending portion of the van Deemter curve is fairly flat at higher velocities than u opt , then the loss in efficiency will be small and well worth the saving in separation time.…”

Diffusion coefficients of gases in liquids and partition coefficients in gas-liquid interphases by reversed-flow gas chromatography

“…In the absence of other processes, the diffusion band can be used to measure accurately the diffusion coefficient of the solute into the carrier gas (17)(18)(19), or other quantities pertaining to it (20,21). When a rate process or an equilibrium state involving one or more solutes is taking place inside the diffusion column, the diffusion band is distorted by that process and this distortion, rather than the distortion of an elution band, is used to measure various physicochemical quantities, like adsorption equilibrium constants (22), rates of drying of catalysts (23), mass transfer and partition coefficients across phase boundaries (24-28), adsorption, desorption and reaction rate constants (29, 30), activity coefficients in solutions (31)(32)(33), interaction of the solid components in a solid adsorbent (34), thermodynamic functions of polymer-solvent systems (35), solubility and interaction parameters in liquid mixtures (36), and finally obstructive factors and porosity in solid beds (37).…”

Συγχρονος Χρωματογραφικος Προσδιορισμος Σταθερων Ταχυτητας, Συντελεστων Μεταφορας Μαζας Και Σταθερων Ισορροπιας Προσροφησεως Σε Καταλυτικες Και Αεριου - Στερεου Αντιδρασεις

“…(6.30), με το Α να δίνεται από την Εξ. Τα αποτελέσματα αυτά έχουν ήδη δημοσιευθεί [40]. υπολογίζουμε το β (ß=B/r 2 ), όπου r 2 είναι η απολύτως μικρότερη τιμή της εξίσωσης [43,47].…”

Fundamental Relationships of Chromatography

“…The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67]. The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67].…”

“…For gas chromatography a velocity of about 2 ■*opt i called the practical operating gas velocity, is frequently recommended [67]. Provided that the ascending portion of the van Deemter curve is fairly flat at higher velocities than u opt , then the loss in efficiency will be small and well worth the saving in separation time.…”

Diffusion coefficients of gases in liquids and partition coefficients in gas-liquid interphases by reversed-flow gas chromatography

“…In the absence of other processes, the diffusion band can be used to measure accurately the diffusion coefficient of the solute into the carrier gas (17)(18)(19), or other quantities pertaining to it (20,21). When a rate process or an equilibrium state involving one or more solutes is taking place inside the diffusion column, the diffusion band is distorted by that process and this distortion, rather than the distortion of an elution band, is used to measure various physicochemical quantities, like adsorption equilibrium constants (22), rates of drying of catalysts (23), mass transfer and partition coefficients across phase boundaries (24-28), adsorption, desorption and reaction rate constants (29, 30), activity coefficients in solutions (31)(32)(33), interaction of the solid components in a solid adsorbent (34), thermodynamic functions of polymer-solvent systems (35), solubility and interaction parameters in liquid mixtures (36), and finally obstructive factors and porosity in solid beds (37).…”

Συγχρονος Χρωματογραφικος Προσδιορισμος Σταθερων Ταχυτητας, Συντελεστων Μεταφορας Μαζας Και Σταθερων Ισορροπιας Προσροφησεως Σε Καταλυτικες Και Αεριου - Στερεου Αντιδρασεις

“…(6.30), με το Α να δίνεται από την Εξ. Τα αποτελέσματα αυτά έχουν ήδη δημοσιευθεί [40]. υπολογίζουμε το β (ß=B/r 2 ), όπου r 2 είναι η απολύτως μικρότερη τιμή της εξίσωσης [43,47].…”

Fundamental Relationships of Chromatography

“…The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67]. The obstruction factor is a dimensionless quasi-constant that is not totally independent of the mobile phase velocity [65][66][67].…”

“…For gas chromatography a velocity of about 2 ■*opt i called the practical operating gas velocity, is frequently recommended [67]. Provided that the ascending portion of the van Deemter curve is fairly flat at higher velocities than u opt , then the loss in efficiency will be small and well worth the saving in separation time.…”

Diffusion coefficients of gases in liquids and partition coefficients in gas-liquid interphases by reversed-flow gas chromatography

“…In the absence of other processes, the diffusion band can be used to measure accurately the diffusion coefficient of the solute into the carrier gas (17)(18)(19), or other quantities pertaining to it (20,21). When a rate process or an equilibrium state involving one or more solutes is taking place inside the diffusion column, the diffusion band is distorted by that process and this distortion, rather than the distortion of an elution band, is used to measure various physicochemical quantities, like adsorption equilibrium constants (22), rates of drying of catalysts (23), mass transfer and partition coefficients across phase boundaries (24-28), adsorption, desorption and reaction rate constants (29, 30), activity coefficients in solutions (31)(32)(33), interaction of the solid components in a solid adsorbent (34), thermodynamic functions of polymer-solvent systems (35), solubility and interaction parameters in liquid mixtures (36), and finally obstructive factors and porosity in solid beds (37).…”

Συγχρονος Χρωματογραφικος Προσδιορισμος Σταθερων Ταχυτητας, Συντελεστων Μεταφορας Μαζας Και Σταθερων Ισορροπιας Προσροφησεως Σε Καταλυτικες Και Αεριου - Στερεου Αντιδρασεις

“…(6.30), με το Α να δίνεται από την Εξ. Τα αποτελέσματα αυτά έχουν ήδη δημοσιευθεί [40]. υπολογίζουμε το β (ß=B/r 2 ), όπου r 2 είναι η απολύτως μικρότερη τιμή της εξίσωσης [43,47].…”