Quantifying extra interaction forces in charged colloidal dispersions from frontal ultrafiltration experiments
Review articleOpen access
Abstract:

AbstractA method for determining extra non-Derjaguin–Landau–Verwey–Overbeek (DLVO) interaction forces for electrostatically stabilised colloidal systems from frontal ultrafiltration data has been developed. The method is based on a previously developed analysis of frontal ultrafiltration and osmotic pressure data. The extra non-DLVO interaction forces for silica were incorporated into a dynamic ultrafiltration model by way of a power law description to more accurately predict filtration rates at low ionic strengths (<0.03 M) where deviations from experimental filtration rates were observed. As the ionic strength was decreased a long-range attraction was observed. The osmotic pressure data indicated that the system seemingly jumped to an ordered structure with a volume fraction of ∼0.5, indicating that a phase transition had occurred. The method requires only simple apparatus, small sample quantities, short preparation times and allows quantification of extra interaction forces for a wide concentration range. The experimentally determined extra interaction forces have been compared with the predictions of two characteristic representatives of recent theoretical descriptions of non-DLVO interactions in concentrated colloidal systems. Neither of the theoretical descriptions could account for the experimental data.

Request full text

References (0)

Cited By (0)

No reference data.
No citation data.
Advertisement
Join Copernicus Academic and get access to over 12 million papers authored by 7+ million academics.
Join for free!