Seyed Reza Shadizadeh - Professor, Department of Petroleum Engineering, Petroleum University of Technology, Abadan, Iran
Amin Derakhshan - M.S. Student, Department of Petroleum Engineering, Petroleum University of Technology, Abadan, Iran

Oil recovery from oil-wet carbonate rock is a significant challenge in the oil industry. The present study investigates the influence of the natural surfactant Hawthorn leaves extract (HLE) on oil recovery from carbonate rock. Two chemical surfactants, sodium dodecyl sulfate (SDS) and dodecyl tri methyl ammonium bromide (DTAB), were used to validate and compare oil recovery with the new natural surfactant HLE. A wettability alteration test using the contact angle method, an interfacial test (IFT) using pendant drop, and core flooding were employed to investigate the behavior of the surfactants on oil recovery. The experimental results show that the critical micellar concentration (CMC) point of different concentrations of HLE, SDS, and DTAB solution occurs at ۳.۲۵, ۳.۰۰, and ۴.۰۶ wt %, respectively. In wettability alteration, the natural surfactant HLE is more effective than other chemical surfactants (SDS and DTAB) at the CMC point. As observed, the contact angle of the carbonate pellet and the HLE at the CMC point is ۸۶°, and this angle for SDS and DTAB is ۱۱۲° and ۹۲°, respectively. The core flooding results show that the oil recovery factor improves from ۳۷% with water flooding to ۴۷.۶% with SDS, ۵۶.۲% with DTAB, and ۵۴.۷% with HLE. The results prove that this new natural surfactant (HLE) can be used as a novel surfactant for the chemically enhanced oil recovery process in carbonate oil reservoirs. HLE has beneficial effects in oil recovery because of its environment friendly compared to SDS and DTAB.

Contact angle, EOR, Hawthorn Leaves Extract, IFT, Wettability Alteration