Adsorption and molecular rearrangement of amphoteric species at oil-water interfaces.

The formation of stable water-in-petroleum emulsions is a costly challenge when transporting, processing, and refining heavy crude oil and bitumen. The stability of these emulsions is attributed to interfacial films with well-documented viscoelastic properties that are known to vary with concentration, solvent quality, and asphaltene chemistry. In this study, we explore the impact of aqueous phase pH and salinity on the transient interfacial rheological properties of asphaltenic films.

Water-in-model oil emulsions studied by small-angle neutron scattering: interfacial film thickness and composition.

The ever-increasing worldwide demand for energy has led to the upgrading of heavy crude oil and asphaltene-rich feedstocks becoming viable refining options for the petroleum industry. Traditional problems associated with these feedstocks, particularly stable water-in-petroleum emulsions, are drawing increasing attention. Despite considerable research on the interfacial assembly of asphaltenes, resins, and naphthenic acids, much about the resulting interfacial films is not well understood.

Correlation of diafiltration sieving behavior of lysozyme-BSA mixtures with osmotic second virial cross-coefficients.

The role of protein-protein interactions in membrane separations of protein mixtures remains incompletely understood, largely due to the difficulty of characterizing protein self- and, especially, cross-association. Recently, a novel technique, cross-interaction chromatography, has been developed to measure weak protein cross-association in terms of the osmotic second virial cross-coefficient. In this work the relationship between protein cross-association and the sieving behavior of lysozyme in the presence of BSA has been investigated.