Synthesis, characterization and enhanced oil recovery potential analysis through simulation of a natural anionic surfactant

Abstract

Enhanced oil recovery (EOR) especially surfactant slug injection has received a great attention as an oil recovery technique. Surfactants are capable in reducing the interfacial tension (IFT) and altering the wettability of rock from subsurface reservoir. Here, a new anionic surfactant was synthesized from Madhuca longifolia (Mahua) oil. The surfactant was characterized using FTIR, GC–MS, FE-SEM and EDX analysis and tested rigorously using IFT, wettability and flooding experiments for its application in EOR. The surfactant showed an ultralow IFT value around 1 × 10−2 at optimal salinity. Thermodynamic parameters were calculated using surface tension as a function of temperature and the studies showed that adsorption of molecules at the interface is favorable over micellization. The surfactant was found to be thermally stable by TGA analysis for its application at high temperature reservoir conditions. It showed the ability to alter the wettability of oil-wet sandstone rock surface to water-wet. The core-flooding experiments were conducted using individual surfactant slug and surfactant-polymer slug injection, which showed an additional recovery of almost 20% over convention water flooding. The experimental results were simulated using computational fluid dynamics (CFD) analysis. The results obtained after simulation study and core-flooding experiment results are very much comparable. The comprehensive evaluation of thermal, interfacial and oil recovery studies provides grounds for potential application in EOR.