Department of Chemical Engineering

Permanent URI for this collectionhttp://localhost:4000/handle/123456789/1923

Browse

Search Results

Now showing 1 - 2 of 2
  • Item
    Integral method of analysis for combined concentration polarization and pore flow model for prediction of the performance of a nanofiltration membrane
    (ACS, 2019-09) Bhattacharjee, Saikat
    A coupled concentration polarization and pore flow model was used to predict the transport characteristics of a monovalent salt through a nanofiltration membrane. The concentration polarization in the flow channel was modeled using an integral method under the framework of boundary layer analysis. The extended Nernst–Planck equation was used to quantify the ion transport through the membrane pores. Ion partitioning across the solution phase and in the membrane pore was modeled using the Donnan exclusion principle including the steric hindrance. The membrane pore charge density was calculated for different membranes. The contributions of convection, diffusion, and electromigration toward the solute flux within the membrane pore were estimated. The calculated permeate flux and the solute concentration in permeate were compared with the experimental data available in the literature and were found to be in good agreement, indicating validation of the developed model.
  • Item
    Electro-kinetically enhanced mass transport of charged macro-solutes through a microchannel with porous walls
    (Wiley, 2022-08) Bhattacharjee, Saikat
    Electrokinetics of the solute transport across the porous walls of micro channel is important from its practical application but less explored. Transport of the charged macro-solutes across perm-selective walls in a microchannel is investigated. The extended Nernst–Planck equation describes the charged macro-solutes distribution in the mass transfer boundary layer over the porous wall. The transverse electromigration of the charged macro-solute either augments or suppresses the concentration polarization and the permeation rate depending on the wall and solute surface potential (attractive or repelling). The wall potential is screened due to the electrical double layer interaction of the wall and charged solute. It is observed that the charged solute concentration over the channel wall enhances by two times in case of oppositely charged interactions (unlike solute and channel wall) compared to like charges. The findings of this study can facilitate understanding of electrokinetic based drug delivery and separation systems involving charged solutes.