High-Temperature Core Flood Investigation of Nanocellulose as a Green Additive for Enhanced Oil Recovery.

Recent studies have discovered a substantial viscosity increase of aqueous cellulose nanocrystal (CNC) dispersions upon heat aging at temperatures above 90 °C. This distinct change in material properties at very low concentrations in water has been proposed as an active mechanism for enhanced oil recovery (EOR), as highly viscous fluid may improve macroscopic sweep efficiencies and mitigate viscous fingering. A high-temperature (120 °C) core flood experiment was carried out with 1 wt.

CO₂ in Lyotropic Liquid Crystals: Monoethanolamine-Facilitated Uptake and Swelling.

Ternary systems consisting of amphiphilic block copolymers/water/monoethanolamine (MEA) have been studied as potential solvents for carbon capture and storage (CCS). The phase behavior of two poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) copolymers with average compositions (EO)₈(PO)(EO)₈ (L92) and (EO)₃(PO)(EO)₃ (L81) have been investigated by cross-polarized visual observation and small angle X-ray scattering (SAXS). The respective ternary phase diagrams have been studied for systems containing MEA and the equivalent systems containing CO₂-loaded MEA.

CO₂ in Lyotropic Liquid Crystals: Phase Equilibria Behavior and Rheology.

The CO₂ absorption of liquid crystalline phases of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (Pluronic L92, (EO)₈(PO)(EO)₈), monoethanolamine (MEA), and water, with a composition of 60% L92/10% MEA/30% water has been investigated to assess potential use in carbon capture and storage applications. Vapor⁻liquid equilibrium data of the liquid crystalline system with CO₂ was recorded up to a CO₂ partial pressure of 6 bar, where a loading of 38.6 g CO₂/kg sample was obtained.

Heavy crude oils/particle stabilized emulsions.

Fluid characterization is a key technology for success in process design for crude oil mixtures in the future offshore. In the present article modern methods have been developed and optimized for crude oil applications. The focus is on destabilization processes in w/o emulsions, such as creaming/sedimentation and flocculation/coalescence.

Structure of nanofibrillated cellulose layers at the o/w interface.

The nature of layers formed by cellulose nanofibrils that had been surface modified (hydrophobized) at the oil/water (o/w) interface was investigated. The aim of the study was to clarify the mechanism underlying the excellent ability of these nanoparticles to stabilize emulsions. Layers of hydrophobized nanofibrillated cellulose spread at the o/w interface were deposited on glass slides by the Langmuir-Blodgett deposition technique.

Hydrophobic monolayer preparation by Langmuir-Blodgett and chemical adsorption techniques.

Alkylsiloxane and perfluoroalkylsiloxane monolayers are prepared on siliceous surfaces using the techniques of Langmuir-Blodgett deposition and solid-liquid chemical adsorption. Acid-catalyzed hydrolysis and polycondensation reactions provide two-dimensional siloxane networks at the liquid-vapor interface, which can be compressed to mean molecular areas of approximately 22 and approximately 32 A(2) for pendent hydrocarbon and fluorocarbon chains, respectively. Subsequent Langmuir-Blodgett transfer onto glass substrates at moderate surface pressures leads to compact monolayers for single-component precursors, while mixed alkyl- and perfluoroalkylsilanes produce nonhomogeneous films characterized by transfer ratios greater than unity.