(630f) Functional Nanomaterials for OIL and Gas Discovery and Recovery Applications

Today, the potential of functional nanoparticles and nanostructured materials to transform key upstream applications in the oil industry is evident. Functional nanoparticles can be engineered to traverse the reservoir while reporting their location, recording key reservoir rock and fluid parameters, and actively mobilizing oil. They enable target-delivery of chemical treatments and sensors deep in the reservoir and can be designed to migrate autonomously via harvesting the surrounding natural or induced solute or chemical gradients. Thus, they can substantially improve reservoir characterization and recovery of its target resources without excessive use of water and chemicals, and with minimal pumping energy.

The major challenges to maximizing the benefits of nanoparticle-based technologies in upstream oil applications can be summarized as: 1) lack of long-term stability and mobility of nanoparticles under typical oil reservoir conditions (usually temperatures exceeding 100 °C, salinities between 50,000 and 220,000 ppm, and pressures exceeding 3000 psi), 2) low-cost prerequisite due to the significantly large amounts needed to interrogate pore volumes typical to the reservoirs (millions of cubic meters), and 3) difficulty to precisely characterize the nanomaterials and test their performance under typical reservoir conditions.

In this article, we present three of our successful oil reservoir nanoagents; A-Dots, Nano-Surfactants, and Magnetic Nano-Mappers. The synthesis of these nanoagents and results of experiments to characterize their nature and behavior under typical reservoir conditions are presented.

A-Dots are carbon dots that are persistently stable at high salinity and elevated temperature. They are optically detectable at low concentrations and can migrate efficiently in the reservoir between injectors and producers. They thus allow establishing “communications” between injectors and producers for improved management of the reservoir. Nano-surfactants are 10 to 60 nm nanostructured particles of the seawater-insoluble petroleum sulfonate salt surfactants, stabilized in seawater by by cocamidopropyl hydroxysultaine zwitterionic co-surfactant molecules. They showed resilient colloidal stability in seawater at elevated temperatures (up to 100 °C) for several months and reduced the seawater-crude oil interfacial tension (IFT) by three orders of magnitude. Thus, nano-transformation of the seawater-insoluble, yet highly efficient, abundant, and inexpensive surfactants enabled their utilization in oil recovery applications in high salinity and temperature oil reservoirs. Magnetic Nano-Mappers are coated magnetic nanoparticles that are colloidally and chemically stable under reservoir conditions. They enhance the magnetic permeability contrast between water and oil, thus allow in-situ monitoring of the oil-water interface using EM surveillance for optimal waterflooding operations.