Effect of mass-transfer coefficients on the elution of a binary mixture in nonlinear liquid chromatography

Both Henry's constants and volumetric mass transfer coefficients (KLa) of eight priority chlorinated organic compounds including 1,1-dichloroethene, methylene chloride, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and 1,4-dichlorobenzene in an air stripping packed column were investigated in this study. The liquid and gas phase EPICS (Equilibrium Partition in Closed System) and direct calculating methods were applied to determine the Henry's constants of VOCs. The interference of co-solute on Henry's constants was also investigated. Experimental results indicated that decrease in Henry's constants of VOCs was observed in the presence of humic acid but no apparent effect on Henry's constants was detected when there was NaCl and surfactant in solution. Four different configurations of packing media including Intalox Saddle, Super Intalox Saddle, Telleret, and Hedgehog made of polypropylene were respectively packed in the air stripping tower and investigated in the study. The dependence of hydraulic loading, air-water ratio, and configurations of packing media on mass transfer coefficients of VOCs was discussed.

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Transport of chlorinated hydrocarbons between sewage and sewer atmosphere

Water Science & Technology ◽

10.2166/wst.1996.0476 ◽

1996 ◽

Vol 34 (3-4) ◽

pp. 557-564 ◽

Cited By ~ 2

Author(s):

Bettina S. Haas ◽

Reimer Herrmann

Keyword(s):

Mass Transfer ◽

Aromatic Compounds ◽

Chlorinated Hydrocarbons ◽

Transfer Coefficients ◽

Mass Transfer Coefficients ◽

Sewerage System ◽

Mass Fluxes ◽

Single Compound

Sewage containing volatile contaminants is a potential VOC-source in cities. Thus we tried to evaluate volatilization out of the sewerage system by measurements of contaminants in sewer gas and sewage. Our results from a medium sized town with little industry showed that sewer gas is mainly contaminated with alkanes, small aromatic compounds and chlorinated hydrocarbons. For three chlorinated hydrocarbons (chloroform, trichloroethene, tetrachloroethene) we determined mass transfer coefficients out of sewage and used these data to estimate mass fluxes from sewage and emissions out of the sewerage system for two sewer stretches. Considerable emission of chlorinated hydrocarbons from sewage, i.e. fluxes of some 10 to 100 g per m2·d, occurred only when the contaminant input via sewage was between some g and mg per litre for a single compound. For concentrations that were about 3 orders of magnitude less, emissions were negligible.

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The calculation of mass transfer coefficients and of axial dispersion coefficients from concentration profiles

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19653822 ◽

1965 ◽

Vol 30 (11) ◽

pp. 3822-3833 ◽

Cited By ~ 9

Author(s):

V. Rod

Keyword(s):

Mass Transfer ◽

Axial Dispersion ◽

Concentration Profiles ◽

Transfer Coefficients ◽

Dispersion Coefficients ◽

Mass Transfer Coefficients

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Mass Transfer in Liquid in an Apparatus with Mobile Packing. Application of a Dispersion Model

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19931078 ◽

1993 ◽

Vol 58 (5) ◽

pp. 1078-1086

Author(s):

Zdeněk Palatý

Keyword(s):

Experimental Data ◽

Mass Transfer ◽

Empirical Equation ◽

Dispersion Model ◽

Transfer Coefficients ◽

Mass Transfer Coefficients

The paper deals with the mass transfer in a liquid on a plate with mobile packing. A procedure has been suggested which enables estimation of the mass transfer coefficients from experimental data considering the dispersion flow of the liquid. The results obtained from the desorption of CO2 from water are presented graphically and in the form of empirical equation.

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On the convective diffusion under partial slip at wall

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19890967 ◽

1989 ◽

Vol 54 (4) ◽

pp. 967-980 ◽

Cited By ~ 3

Author(s):

Ondřej Wein ◽

Petr Kučera

Keyword(s):

Mass Transfer ◽

Numerical Solution ◽

Analytic Solution ◽

Convective Diffusion ◽

Linear Velocity ◽

Partial Slip ◽

Accurate Calculation ◽

Transfer Coefficients ◽

Empirical Formulas ◽

Mass Transfer Coefficients

Extended Leveque problem is studied for linear velocity profiles, vx(z) = u + qz. The existing analytic solution is reconsidered and shown to be inapplicable for the accurate calculation of mean mass-transfer coefficients. A numerical solution is reported and its accuracy is checked in detail. Simple but fairly accurate empirical formulas are suggested for the calculating of local and mean mass-transfer coefficients.

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A Method for Estimating Mass Transfer Coefficients in a Packed Column Using Reactive Absorption Data

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20050383 ◽

2005 ◽

Vol 70 (3) ◽

pp. 383-402

Author(s):

Valery A. Danilov ◽

Il Moon

Keyword(s):

Experimental Data ◽

Mass Transfer ◽

Optimization Technique ◽

Packed Column ◽

Effective Area ◽

Transfer Coefficients ◽

Mass Transfer Coefficients ◽

Model Calculations ◽

Unit Model ◽

Reactive Absorption

This paper is devoted to the development of a new method for estimating mass transfer coefficients and effective area in packed columns in the case of reactive absorption. The method is based on a plug-flow model of reactive absorption of carbon dioxide with sodium hydroxide solution. The parameter estimation problem is solved using an optimization technique. Some mass transfer parameters are found to be correlated. Global sensitivity analysis by Sobol's technique showed that the unit model with the defined objective function is sensitive to the estimated parameter. Case studies of reactive absorption with different packings illustrate application of the proposed method for estimating mass transfer coefficients and effective area from column operation data. The model calculations are compared with experimental data obtained by other authors. The concentration profiles calculated by the unit model with the estimated parameters are shown to match well with experimental profiles from literature. A good agreement between estimated values and experimental data from literature confirms the applicability of this method.

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