High temperature stability and low adsorption of sub-100 nm magnetite nanoparticles grafted with sulfonated copolymers on Berea sandstone in high salinity brine

Abstract

The synthesis of polymer grafted nanoparticles that are stable at high salinities and high temperature with low retention in porous media is of paramount importance for subsurface applications including electromagnetic imaging, enhanced oil recovery and environmental remediation. Herein, we present an improved approach to synthesize and purify sub-100 nm IONPs grafted with a random copolymer poly(AMPS-co-AA) (poly(2-acrylamido-3methylpropanesulfonate-co-acrylic acid)) by means of catalyzed amide bond formation at room temperature. The improved and uniform polymer grafting of magnetic nanoparticles led to colloidal stability of IONPs at high temperature (120 °C) in API for a month. The transport behavior of the polymer grafted IONPs was investigated in crushed and in consolidated Berea sandstone. The high poly (AMPS-co-AA) polymer level on the surface (~34%) provided electrosteric stabilization between the NPs and weak interactions of the NPs with anionic silica and sandstone surfaces. This behavior was enabled by low affinity of Ca 2+ towards the highly acidic AMPS monomers thus enabling strong solvation in API brine. In crushed Berea sandstone, the retention was reduced by three fold and nine fold relative to our earlier studies, given the improvements in the grafted polymer layer. For intact core flood experiments in Berea sandstone carried out at elevated temperature (65 o C) and pressure (1000 psi net confining stress), the retention was 519 µg/g, comparable to the value for crushed Berea sandstone. Furthermore, the addition of a relatively small amount (0.1% v/v) of commercially available sacrificial polymer (e.g., HEC-10) further reduced IONP retention to 252 µg/g or 0.17 mg/m 2 by blocking retentive sites.

Propagation of Surfactant‐Dispersed Multiwalled Carbon Nanotubes in Porous Media

“…On the contrary, crushed Berea sand has a variety of complex compositions, including 5–8% clay minerals, such as illite, chlorite, and kaolinite. The higher retention of MWNT in crushed Berea sand is believed to be a result of the presence of clay fines, which is known as an extremely retentive media for surfactants and nanoparticles (Fang et al, ; Iqbal et al, ). In addition, no channeling was observed in the sand pack.…”

“…In a modified scenario, a robust foam booster, AOS, was used to replace IOS. Before the introduction of MWNT dispersion, the sand pack column was preflushed with 3 PV of HEC at 800 mg L −1 , which was aimed to diminish surfactant adsorption by covering the sand surface adsorptive sites (Iqbal et al, ) while maintaining a stable foam by reducing liquid drainage. The control group adopted a surfactant‐only reagent, while the experiment group used surfactant‐MWNT as a foam booster reagent.…”

“…Through the whole experiment, the fluid was controlled at a constant flow rate of 0.3 mL min −1 (corresponding to a pore water velocity of 2.6-2.8×10 −3 cm s −1 ) via a peristaltic pump (Masterflex). After dry packing of unconsolidated sand into a chromatographic glass column (Kimble Chase), (Iqbal et al, 2017) 83-88 2 5-7 2 -4 1 2 -3 Crushed Indiana limestone (Tagavifar et al, 2018) 0.9 97.7 0.2 0.6 0.6…”

Bio-nano interactions: binding proteins, polysaccharides, lipids and nucleic acids onto magnetic nanoparticles

“…The IONPs functionalized with TRIS produced the greatest amounts of bound ODN, probably attributable to a high surface area [ 17 ]. Although not mentioned, as zeta potential measurements are not included in their study, commercially used silica coated nanoparticles are well known to present negative charges in a wide range of pH [ 124 ]; however these nanoparticles obtained the largest amount of adsorbed negatively charged pDNA. At pH 4.0, the zeta potential seems to be close to a neutral charge (~ − 15 mV) and consequently electrostatic repulsions no longer play the primary role in the interaction between the polyanion DNA and the nanoparticles, being replaced by hydrogen bonds.…”

Ultra-Stable Silica Nanoparticles as Nano-Plugging Additive for Shale Exploitation in Harsh Environments

“…The poly (3-sulfopropyl methacrylate potassium salt) p(SPMA) with many sulfonic groups (negatively charged groups) has strong hydration capability and can resist flocculation at high temperatures. Thus, p(SPMA) can be fully stretched in aqueous solution and provide steric and electrostatic repulsion to stabilize nanoparticle suspensions [30]. Scheme 1.…”