A multicomponent nanocapsule composition comprising a core particle, an oil phase encapsulating the core particle, and an aqueous phase in which the encapsulated core particle is suspended is provided. The porous particle includes a cationic surfactant encapsulated in a porous particle. The oil phase includes an anionic surfactant and a zwitterionic surfactant. A method of making a multicomponent nanocapsule composition is also provided. A method of treating a hydrocarbon-bearing formation with the multicomponent nanocapsule composition is provided. The method may include providing a multicomponent nanocapsule composition, introducing the multicomponent nanocapsule composition into the hydrocarbon-bearing formation, displacing hydrocarbons from the hydrocarbon-bearing formation by contacting the multicomponent nanocapsule composition with the hydrocarbons, and recovering the hydrocarbons.

A method for modifying surface wettability of a surface of a solid substrate may include contacting the surface of the solid substrate with a brine solution containing carbon nanodots. The carbon nanodots may have carbon, oxygen, nitrogen, and hydrogen as constituent elements and may include one or more functional groups disposed at outer surfaces of the carbon nanodots. The brine solution has a salinity of greater than 30,000 TDS. A concentration of carbon nanodots in the brine solution is less than or equal to 500 ppmw. Contacting the solid substrate with the brine solution comprising the carbon nanodots is characterized by a contact duration, a contact volume, or both, that is sufficient to reduce the oil wettability of the surface of the solid substrate by at least 15%, as defined by a contact angle of a crude oil droplet contacted with the surface of the solid substrate.

A tight oil reservoir CO.sub.2 flooding multi-scale channeling control system and a preparation method, including nanoscale CO.sub.2 responsive worm-like micellar systems and micron-scale CO.sub.2 responsive dispersion gel, are provided. The nanoscale CO.sub.2 responsive worm-like micelle system is prepared by CO.sub.2 reactive monomers and organic anti-ion monomers stirred in water. The micron-scale CO.sub.2 responsive dispersion gel is made of acrylamide, a responsive monomer, a silane coupling agent modified hydroxylated multi-walled carbon nanotubes as raw materials, cross-linked in water. The tight oil reservoir CO.sub.2 multi-scale channel control system, has strong flow control ability during CO.sub.2 displacement, and high-strength carbon nanotubes are introduced into the micro-scale CO.sub.2 responsive dispersion gel, which effectively improves the strength and long-term stability of the dispersion gel, significantly enhances the sealing effect on cracks, and after displacement of the CO.sub.2 of the system, the worm-like micelles revert to spherical micelles with good responsive reversibility.

Coated proppants include a proppant particle, a surface copolymer layer surrounding the proppant particle, and a resin layer surrounding the surface copolymer layer. The surface copolymer layer includes a copolymer of at least two monomers chosen from styrene, methyl methacrylate, ethylene, propylene, butylene, imides, urethanes, sulfones, carbonates, and acrylamides, where the copolymer is crosslinked by divinyl benzene. The resin layer includes a cured resin. Methods of preparing the coated proppants include preparing a first mixture including at least one polymerizable material, an initiator, and a crosslinker including divinyl benzene; contacting the first mixture to a proppant particle to form a polymerization mixture; heating the polymerization mixture to cure the polymerizable material and form a polymer-coated particulate; preparing a second mixture including the polymer-coated substrate, an uncured resin, and a solvent; and adding a curing agent to the second mixture to cure the uncured resin and form the coated proppant.

The present invention provides a device, system, and method that eliminates the short-circuiting and improves energy sweep in geothermal reservoirs.

A method to reduce the deposition of solid sulfur (S.sub.8(s)) in a natural gas producing well is described where hydrophobic surface modified silica nanoparticles are added into the tubing string, and the hydrophobic surface modified silica nanoparticles interact with the gaseous sulfur (S.sub.8(g)) present in the gas resulting in the reduction of the deposition of solid sulfur (S.sub.8(s)), The hydrophobic surface modified silica nanoparticles are selected from the group that includes silica, alumina and silica-aluminate. The hydrophobic surface modified silica nanoparticles may be added to the tubing string either dry or mixed first into a carrier fluid, which carrier fluid may be a liquid or a gas.

Graphene quantum dots are functionalized by covalently bonding a corrosion inhibitor molecule thereto. In a useful method, a corrosion inhibitor compound is blended with a graphene quantum dot-tagged corrosion inhibitor compound, and the blend is applied to a metal surface, such as the interior of a carbon steel pipe. The blend inhibits corrosion arising from contact with produced water generated by hydrocarbon recovery from one or more subterranean reservoirs. The produced water having the blend dispersed therein is irradiated with a source of light having a selected first range of wavelengths, and the luminescent emission of the graphene quantum dot-tagged corrosion inhibitor is measured at a selected second range of wavelengths, thereby providing for real-time measurement of corrosion inhibitor concentration within the pipe.

A chemical gel system having a polymer and a silicon oxide Janus nanosheets crosslinker for treating thief zones in carbonate formations. The polymer and silicon oxide Janus nanosheets crosslinker may form a crosslinked polymer gel to reduce or prevent water production via thief zones during hydrocarbon production. The silicon oxide Janus nanosheets crosslinker includes a first side having negatively charged functional groups and a second side having amines. The negatively charged functional groups may include negatively charged oxygen groups and hydroxyl groups. Methods of reducing water production in a thief zone using the silicon oxide Janus nanosheets crosslinker and methods of manufacturing the silicon oxide Janus nanosheets crosslinker are also provided.

Provided herein are drilling muds, including water-based drilling muds. The components of the drilling muds are a degradable fluid loss additive, for example, synthetic degradable nanoparticles, a clay mineral, for example, a smectite, and a base fluid, for example, water. Also provide are methods for preventing leak-off during a drilling operation and for automatically cleaning-up filter cake after completion of a drilling process both of which utilize the drilling muds and water-based drilling muds.

Disclosed are a high-temperature-resistant tertiary amine-grafted silica nano-plugging agent and water-based drilling fluids, relating to oil-gas field drilling. The nano-plugging agent is prepared from a hydrazine compound, a diallyl compound, an enamine compound, silica particle, and an amino-containing silane coupling agent by stepwise reaction. The nano-plugging agent has a grain size of 58-280 nm.