Oil Mobilization Potential of a Novel Anionic Karanj Oil Surfactant: Interfacial, Wetting Characteristic, Adsorption, and Oil Recovery Studies
Himanshu Kesarwani, Amit Saxena, Neha Saxena, Shivanjali Sharma
Abstract
The most widely accepted technique of tertiary recovery is alkaline surfactant polymer (ASP) flooding. In situ surfactants are formed owing to the interaction of alkali with the carboxylic group present in crude oil. The polymer affects mobility, while the surfactant reduces interfacial tension (IFT). The synergistic effects of these phenomena aid in the efficient displacement of crude oil. Commercial surfactant has been used in ASP flooding, but its high cost has always been a significant economic concern for its implementation. The present work focuses on the development and characterization of a novel biodegradable surfactant from the Karanj oil and evaluates its potential as a prospective surfactant for ASP flooding. A novel surfactant was synthesized by the esterification and then sulfonation of Karanj oil. The product was characterized using Fourier transform infrared (FTIR), gas chromatography–mass spectrometry (GCMS), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), and thermogravimetric analysis (TGA). The oil recovery potential of the surfactant was evaluated using an ASP chemical slug. The surfactant was found to be thermally stable up to 300 °C. A minimum IFT of 0.0081 mN/m was achieved with the Karanj oil surfactant at critical micelle concentration (CMC) with 2 wt % salt. The Karanj oil surfactant effectively modified the oil wetting behavior of the sand surface to hydrophilic. The Karanj oil surfactant showed lower adsorption as compared to the conventional anionic surfactant. The sand pack flooding results show that ∼48% of the crude was recovered using water flooding and an additional ∼32% of the crude oil was recovered using the ASP slug designed using the Karanj oil surfactant.