The influence of dissolved gas on the interactions between surfaces of different hydrophobicity in aqueous media Part II
Date
1999
Authors
Stearnes, J.
Ralston, J.
Hayes, R.A.
Fornasiero, D.
Gong, W.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Physical Chemistry, Chemical Physics - PCCP, 1999; 1(11):2799-2803
Statement of Responsibility
Conference Name
DOI
Abstract
The aggregation of smooth hydrophobic and hydrophilic silica particles in the presence of different gases has been investigated at pH 5.6 and 10<sup>-</sup> <sup>4</sup> M KNO<inf>3</inf>, using the attenuated total internal reflectance Fourier transform infrared spectroscopy (ATR-FTIR) technique. The rate of aggregation of methylated silica is enhanced in the presence of dissolved CO<inf>2</inf> but is unaffected by dissolved air, argon or nitrogen. The aggregation of hydrophilic and heat treated dehydroxylated silica is not influenced by any gas tested. For methylated silica, CO<inf>2</inf> adsorbs on to the surface as tiny microbubbles. These microbubbles decrease the colloid stability of the methylated silica particles, overcoming the electrostatic repulsion at pH 5.6 and 10<sup>-4</sup> M KNO<inf>3</inf>. The results obtained are in broad agreement with our previous atomic force microscopy (AFM) investigation of interparticle forces and bubble-particle heterocoagulation studies.
School/Discipline
Dissertation Note
Provenance
Description
Access Status
Rights
Copyright status unknown