Graphene as a Surfactant Carrier: A Performance Study for Enhanced Oil Recovery Applications

Abstract

Abstract Graphene as surfactant carrier material for EOR/IOR is used. Its performance is evaluated through adsorption, desorption, interfacial tension and emulsification studies. Moreover, the kinetic and thermodynamic parameters are identified in order to understand the physicochemical behavior pertaining to its applicability in surfactant flooding. The surfactant carrier, graphene is acquired and its physicochemical behavior is characterized by X-Ray diffraction, Fourier transform infrared spectroscopy, surface area analysis, etc. The uptake capacity of the surfactant is investigated by adsorption and desorption studies at different subsurface conditions. The kinetics of the process are identified to understand the rate and order of the reaction, whereas thermodynamic behavior of the surfactant carrier is evaluated to find its Gibbs free energy, enthalpy, entropy, activation energy, etc. Further, a reduction in interfacial tension and stability of emulsion between crude oil and brine is inspected. The uptake capacity of the surfactant obtained from the adsorption and desorption study confirmed that adequate quantities of surfactant can be transported into the deep subsurface with minimal loss. This infers the requirement of surfactant in lesser quantity when compared to surfactants without any nanocarrier. Similarly, a reduction in interfacial tension and increase in emulsion stability is expected to be increased. Furthermore, graphene shows a remarkable change in hydrophobicity with a change in pH and salinity which indicates that the properties can be suitably tailored as per requirement, making it a good candidate for surfactant EOR/IOR. Also, the obtained thermodynamic data suggest endothermic and spontaneous adsorption behavior, which may be a favorable phenomenon when subjected to the higher subsurface temperature. Graphene as a surfactant carrier and its performance is investigated for the first time rendering it unique for EOR/IOR applicability studies.