Effect of electrostatic interactions on rejection of capsular and spherical particles from porous membranes: theory and experiment. Academic Article uri icon


  • HYPOTHESES: Particle rejection from porous membranes will increase when particle and membrane carry like charges. The influence of charge on particle rejection can be modeled by first solving the Poisson-Boltzmann equation for the electrostatic particle-pore wall interaction energy, enabling one to predict the cross sectional particle concentration in a pore. Rejection coefficients can then be predicted by combining the Boltzmann factor with a hydrodynamic lag coefficient. EXPERIMENTS: Rejection experiments were conducted with three different spherical colloidal silica particles, a spherical virus (PRD1) and gold nanorods of two different aspect ratios (ratio of length to diameter). Track-etched polycarbonate microfiltration and ultrafiltration membranes having nearly parallel pores of cylindrical cross-section were used. Experiments were conducted under conditions where both particle and membrane carried a negative charge as well as under conditions where surface charges had minimal impact. Experiments were designed to cover a broad range of dimensionless particle sizes under conditions when convection dominated particle transport. FINDINGS: Model predictions and experimental measurements demonstrate that particle rejection can be enhanced significantly when particle and pore carry like charges.

published proceedings

  • J Colloid Interface Sci

altmetric score

  • 0.25

author list (cited authors)

  • Agasanapura, B., Baltus, R. E., Tanneru, C. T., & Chellam, S.

citation count

  • 9

complete list of authors

  • Agasanapura, Basavaraju||Baltus, Ruth E||Tanneru, Charan Tej||Chellam, Shankararaman

publication date

  • June 2015