| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 607886 | Journal of Colloid and Interface Science | 2013 | 10 Pages |
Transport of metal oxide nanoparticles in porous rock is of interest for imaging and oil recovery in subsurface reservoirs, which often contain concentrated brine. Various copolymers composed of acrylic acid and either 2-acrylamido-2-methylpropanesulfonate or styrenesulfonate were synthesized and adsorbed on iron oxide nanoclusters to provide colloidal stability and to achieve low adsorption on silica in high salinity brine composed of 8% wt. NaCl + 2% wt. CaCl2. Furthermore, the degree of adsorption of the nanoparticles on silica was controlled by modifying the acrylic acid groups in the copolymers with a series of diamines and triamines to add hydrophobicity. The adsorption on colloidal silica microparticles ranged from <1 mg/m2 for highly charged hydrophilic surfaces on the iron oxide nanoparticles to 22 mg/m2 for the most hydrophobic amine-modified surfaces, corresponding to monolayer coverages that ranged from 0.2% to 11.5%, respectively. The specific adsorption (mg-IO/m2-silica), monolayer coverage, and parameters for Langmuir isotherms were evaluated for various IO nanoclusters as a function of the properties of the copolymers on their surfaces.
Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (153 K)Download as PowerPoint slideHighlights► Adsorption of iron oxide nanoparticles (NPs) on silica measured in brine. ► NPs coated with sulfonated copolymers. ► Adsorption on silica tuned by modifying NP coating with hydrophobic amines. ► Adsorption tuned from <1 mg/m2 to 22 mg/m2 by varying properties of amines. ► NP adsorption on silica followed Langmuir adsorption behavior.
