Ultrafiltration of colloidal dispersions  A theoretical model of the concentration polarization phenomena
(1996) In Journal of Colloid and Interface Science 180(2). p.504518 Abstract
 A general thermodynamic model of the concentration polarization phenomena of colloidal particles at a membrane surface is presented. The model is based on the balance between a thermodynamic force, due to the osmotic pressure gradient, and a frictional force, due to the fluid flow around each particle. A cell model description is used to model the concentration dependence of the thermodynamic force as well as the how properties in the concentrated colloidal solution. Equilibrium thermodynamics of the colloidal system can be used in the cell calculations since local equilibrium is assumed in the neighborhood of each colloidal particle (i.e., in each cell). This means that the concentration dependence of the osmotic pressure can be obtained,... (More)
 A general thermodynamic model of the concentration polarization phenomena of colloidal particles at a membrane surface is presented. The model is based on the balance between a thermodynamic force, due to the osmotic pressure gradient, and a frictional force, due to the fluid flow around each particle. A cell model description is used to model the concentration dependence of the thermodynamic force as well as the how properties in the concentrated colloidal solution. Equilibrium thermodynamics of the colloidal system can be used in the cell calculations since local equilibrium is assumed in the neighborhood of each colloidal particle (i.e., in each cell). This means that the concentration dependence of the osmotic pressure can be obtained, either from an experimental determination or from a theoretical model of the bulk properties of the colloidal system. To exemplify the usefulness of the model when establishing the influence of different operating parameters, such as the transmembrane pressure, the fluid shear, or different solution properties, such as concentration, particle size, pH, and ionic strength, a model system of charged spherical colloidal particles is used. The interaction between the particles is in the presented examples assumed to be a combination of electrostatic interactions, calculated from the PoissonBoltzmann equation, dispersion forces, calculated as additive 1/r(6) interactions, and a hard sphere interaction calculated from the CarnahanStarling equation. (C) 1996 Academic Press, Inc. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/record/3915758
 author
 Jönsson, AnnSofi ^{LU} and Jönsson, Bengt ^{LU}
 organization
 publishing date
 1996
 type
 Contribution to journal
 publication status
 published
 subject
 keywords
 colloids, flow model, osmotic pressure, concentration polarization, ultrafiltration
 in
 Journal of Colloid and Interface Science
 volume
 180
 issue
 2
 pages
 504  518
 publisher
 Elsevier
 external identifiers

 wos:A1996UT35000024
 scopus:0030601127
 ISSN
 10957103
 DOI
 10.1006/jcis.1996.0331
 language
 English
 LU publication?
 yes
 id
 f218defd30204402881e620fc44fdc43 (old id 3915758)
 date added to LUP
 20130702 10:25:33
 date last changed
 20171008 03:40:25
@article{f218defd30204402881e620fc44fdc43, abstract = {A general thermodynamic model of the concentration polarization phenomena of colloidal particles at a membrane surface is presented. The model is based on the balance between a thermodynamic force, due to the osmotic pressure gradient, and a frictional force, due to the fluid flow around each particle. A cell model description is used to model the concentration dependence of the thermodynamic force as well as the how properties in the concentrated colloidal solution. Equilibrium thermodynamics of the colloidal system can be used in the cell calculations since local equilibrium is assumed in the neighborhood of each colloidal particle (i.e., in each cell). This means that the concentration dependence of the osmotic pressure can be obtained, either from an experimental determination or from a theoretical model of the bulk properties of the colloidal system. To exemplify the usefulness of the model when establishing the influence of different operating parameters, such as the transmembrane pressure, the fluid shear, or different solution properties, such as concentration, particle size, pH, and ionic strength, a model system of charged spherical colloidal particles is used. The interaction between the particles is in the presented examples assumed to be a combination of electrostatic interactions, calculated from the PoissonBoltzmann equation, dispersion forces, calculated as additive 1/r(6) interactions, and a hard sphere interaction calculated from the CarnahanStarling equation. (C) 1996 Academic Press, Inc.}, author = {Jönsson, AnnSofi and Jönsson, Bengt}, issn = {10957103}, keyword = {colloids,flow model,osmotic pressure,concentration polarization,ultrafiltration}, language = {eng}, number = {2}, pages = {504518}, publisher = {Elsevier}, series = {Journal of Colloid and Interface Science}, title = {Ultrafiltration of colloidal dispersions  A theoretical model of the concentration polarization phenomena}, url = {http://dx.doi.org/10.1006/jcis.1996.0331}, volume = {180}, year = {1996}, }