Nanofluid of graphene-based amphiphilic Janus nanosheets for tertiary or enhanced oil recovery: High performance at low concentration

TLDR

Improving crude oil recovery by 1 % worldwide would unlock vast resources, yet chemical methods such as surfactants or polymers yield only 10–20 % enhancement and raise serious economic and environmental concerns, and low‑concentration nanoparticle nanofluids (<0.01 wt %) are a promising alternative but achieve less than 5 % efficiency in saline environments. The study aims to evaluate a graphene‑based Janus amphiphilic nanosheet nanofluid for enhanced oil recovery, targeting an efficiency comparable to chemical methods while being economically and environmentally advantageous. The nanofluid consists of graphene‑based Janus amphiphilic nanosheets delivered at low concentration (≤0.01 wt %) in saline environments. The nanofluid achieved about 15.2 % oil recovery, comparable to chemical methods.

Abstract

Significance Improving crude oil recovery by 1% worldwide would result in a huge amount of crude oil resources becoming available. However, the economic and environmental concerns are too serious to ignore when chemical methods (surfactants or polymers flooding, etc.) are used for an average 10–20% enhancement for tertiary oil recovery. Simple nanofluid (containing only nanoparticles) flooding at low concentration (0.01 wt % or less) is a promising alternative, but the efficiency is below 5% in a saline environment (2 wt % or higher NaCl content). We report a simple nanofluid of graphene-based Janus amphiphilic nanosheets for enhanced oil recovery with efficiency of about 15.2%, comparable to chemical methods, which is both economically and environmentally beneficial to the petroleum industry.