Janus nanofluids for enhanced oil recovery

Applying nanomaterials in waterflooding is an emerging research topic in petroleum engineering research. Nanofluids, composed of nanoparticles (NPs) suspended in an aqueous solution, with or without the addition of other chemicals (surfactants or polymers), have received extensive interest by worldwide petroleum researchers because of their high potential for enhanced oil recovery (EOR) application. Various nanomaterials have been formulated and evaluated on EOR processes in laboratory-scale experiments, which revealed the nanofluids as very promising agents for EOR. Janus nanoparticles (JNPs), as a new and special type of NPs, have two or more distinct surfaces, which allow them to have different physical properties and chemical behaviors at the same time. In this chapter, the special features, synthesis methods, advantages, and disadvantages of the Janus nanofluids for use in the enhancement of oil recovery are reviewed. The effects of the Janus nanofluids on the wettability alteration, interfacial tension (IFT) reduction, and viscosity alteration on the enhancement of oil recovery are analyzed. The challenges facing for use of the Janus nanofluids at field-scale operations are also discussed.