Synergistic Collaboration between Regenerated Cellulose and Surfactant to Stabilize Oil/Water (O/W) Emulsions for Enhancing Oil Recovery

Abstract

A stable emulsion can play an important role in displacing oil or controlling reservoir conformance for enhanced oil recovery (EOR) projects. In this work, visual inspection, multiple-light scattering, interfacial tension (IFT), and rheology were used to investigate the synergistic effects of regenerated cellulose and surfactant on oil-in-water emulsions stability and their efficiency in EOR. The results show that adding regenerated cellulose can significantly increase the stability of a surfactant emulsion, while decreasing the diameter, coalescence, and floatation of oil droplets. This can be attributed to the synergistic interactions between cellulose and surfactant, which enable them to form a tighter interface layer and slightly reduce the oil/water (O/W) IFTs. Moreover, in comparison with the surfactant-only systems, the surfactant–cellulose systems exhibit higher viscoelasticity of the continuous phase, as well as better shearing tolerance and self-recovery of emulsions. Ultimately, the microscopic oil displacement experiments demonstrate that the system can efficiently decrease the residual oil saturation after water flooding. These impressive performances make this blended system ideal for use in the chemical flooding process for EOR.

Synergistic Effects between Different Types of Surfactants and an Associating Polymer on Surfactant–Polymer Flooding under High-Temperature and High-Salinity Conditions

“…The IFT decreases sharply but then slightly increase as the surfactant concentration increases. Actually such a slight increase in IFT has been observed in previous studies. ,,,− At extremely low surfactant concentrations, the surfactant molecules exist mainly in solution with very few surfactants absorbing at the oil–water interface. Therefore, the effect of surfactant on oil–water interfacial properties remains very limited.…”

Perspectives in Nanocellulose for Crude Oil Recovery: A Minireview

“…The cellulose/surfactant systems increase shear tolerance and promote smaller droplets in the emulsion, increasing its stability. 114 Unfortunately, the authors did not provide information regarding surface properties or surface chemistry for the nanocellulose.…”

“…Regenerated nanocellulose, after the dissolution of wood pulp in phosphoric acid and homogenization, was used by Li et al to study the stability of o/w Pickering emulsions. , As mentioned above, oxidated NC contains highly hydrophilic cellulose macromolecules with abundant −OPO 3 – and −OH functional groups in addition to an axial hydrophobic face; therefore, it can behave as an o/w emulsifier . Backscattering measurements showed the increased stability of the emulsions and an increase in the droplet size as the cellulose concentration increases.…”

“…Further studies by the same authors demonstrated the synergy between alkylpolyglucoside (surfactant) and regenerated cellulose to increase oil displacement efficiency and recovery in EOR displacement experiments. The cellulose/surfactant systems increase shear tolerance and promote smaller droplets in the emulsion, increasing its stability . Unfortunately, the authors did not provide information regarding surface properties or surface chemistry for the nanocellulose.…”

Design and characterization of oil-in-water nanoemulsion for enhanced oil recovery stabilized by amphiphilic copolymer, nonionic surfactant, and LAPONITE® RD

“…Emulsion ooding can be a promising EOR method that increases the macroscopic and microscopic displacement efficiencies. [27][28][29][30] The transport phenomena of displacement uids containing chemical additives in porous media are important for EOR. Nanoemulsions (NEs) contain small particles and are more stable than ordinary emulsions.…”