Abstract: Novel microemulsion formulations comprising a surfactant or combination of surfactants are disclosed for improved crude oil cleanup or recovery from subsurface geological formations, especially those containing carbonate cements.

Abstract: Novel microemulsion formulations comprising a surfactant or combination of surfactants are disclosed for improved crude oil cleanup or recovery from subsurface geological formations, especially those containing carbonate cements.

Abstract: Embodiments of the present disclosure generally relate to methods and formulations for enhanced oil recovery. In an embodiment, a method for treating oil-containing porous media for oil recovery includes introducing oil-containing porous media with a surfactant formulation described herein. Methods can be utilized for, e.g., wettability reversal or oil recovery. Surfactant formulations are also described.

Abstract: In one embodiment, a method for recovery of an oil from a porous medium comprises contacting the porous medium with an aqueous nanofluid, solubilizing oil from the porous medium via the nanoparticles to form a dispersion comprising the oil and the aqueous nanofluid, and collecting at least some of the dispersion. The aqueous nanofluid may contain a combination of amphiphilic quantum dots and hydrophilic quantum dots, in a continuous phase. At least 90% of the quantum dot nanoparticles may have an aspect ratio of from 1:1 to 1:6. In another embodiment, a method for recovery of an oil from a porous medium includes adding quantum dots to foaming surfactants to enhance foam lamella stability under reservoir conditions and provide conformance and mobility control in porous media and hydraulic fractures.

Abstract: In one embodiment, a method for recovery of an oil from a porous medium comprises contacting the porous medium with an aqueous nanofluid, solubilizing oil from the porous medium via the nanoparticles, thereby forming a dispersion comprising the oil and the aqueous nanofluid, and collecting at least some of the dispersion. The aqueous nanofluid may contain a combination of amphiphilic quantum dots and hydrophilic quantum dots, in a continuous phase. At least 90% of the quantum dot nanoparticles may have an aspect ratio of from 1:1 to 1:6. The dispersion comprising the oil and the aqueous nanofluid may be stabilized via synergistic effects resulting from the combination of amphiphilic quantum dots and hydrophilic quantum dots. In another embodiment, a method for recovery of an oil from a porous medium whereby the quantum dots are added to foaming surfactants to enhance foam lamella stability under reservoir conditions and provide conformance and mobility control in porous media and hydraulic fractures.

Abstract: Methods for evaluating an optimal surfactant structure for oil recovery by systematically evaluating surfactants' phase behavior, cloud point, dynamic interfacial tension, dynamic contact angle, and spontaneous and forced imbibition. In one embodiment, a method for determining an optimal surfactant structure for oil recovery includes the steps of evaluating a surfactant's phase behavior, evaluating the surfactant's solubility, evaluating the surfactant's dynamic interfacial tension in a porous rock sample, evaluating the surfactant's static and dynamic contact angles in the porous rock sample, evaluating the surfactant's spontaneous imbibition in the porous rock sample, and evaluating the surfactant's forced imbibition in the porous rock sample. In one example, the surfactant comprises a polyoxyethylenated (POE) straight-chain alcohol.

Abstract: The present invention relates to methods for evaluating an optimal surfactant structure for oil recovery by systematically evaluating surfactants' phase behavior, cloud point, dynamic interfacial tension, dynamic contact angle, and spontaneous and forced imbibition.

Abstract: Methods for determining an optimal surfactant structure for oil recovery are described. These methods systematically evaluate surfactants' phase behavior at ambient and at reservoir conditions; cloud point from ambient to reservoir conditions; dynamic interfacial tension at ambient and at reservoir conditions, including crude oil bubble images and fitting drop profiles; static contact angles at ambient conditions and dynamic contact angles at reservoir conditions; spontaneous imbibition at ambient conditions; and forced imbibition at reservoir conditions.

Abstract: Methods for determining an optimal surfactant structure for oil recovery are described. These methods systematically evaluate surfactants' phase behavior at ambient and at reservoir conditions; cloud point from ambient to reservoir conditions; dynamic interfacial tension at ambient and at reservoir conditions, including crude oil bubble images and fitting drop profiles; static contact angles at ambient conditions and dynamic contact angles at reservoir conditions; spontaneous imbibition at ambient conditions; and forced imbibition at reservoir conditions.

Abstract: Novel microemulsion formulations comprising a surfactant or combination of surfactants are disclosed for improved crude oil cleanup or recovery from subsurface geological formations, especially those containing carbonate cements.