Experimental Investigation of the Suitability of Surfactants Extracted from Plant Leaves for Enhanced Oil Recovery

The application of natural surfactants in enhanced oil recovery has recently gained popularity due to their environmentally friendly nature and low cost of production. Several natural surfactants have been extracted from plant leaves and tested for interfacial tension reduction and increased oil recovery. However, it is important to evaluate the oil recovery potential of natural surfactants extracted from plant leaves that are abundant and available in each region for easy production. This study evaluates the recovery potential of surfactants produced from Citrus sinensis leaves, Carica papaya leaves, and Garcinia kola leaves due to their saponin contents for enhanced recovery while reducing the cost of conventional surfactants. The plant leaves (Citrus sinensis, Carica papaya, Garcinia kola) were washed, dried for one week, ground, and measured in quantities of 2 grams and 4 grams. The measured quantities were added to 30 ml of hot water, stirred to mix uniformly, and then brine was added to fill up to 1000 ml in the cylinder. The solution was filtered to obtain the surfactant extract. Core samples were saturated with low salinity brine (10,000 ppm) and flooded with crude oil until irreducible water saturation was achieved. The breakthrough time and volume of water and oil recovered were measured. The brine was replaced with the extracted surfactants at concentrations of 2000 ppm and 4000 ppm, and used for flooding. The volume of oil recovered for each surfactant was measured. The results show that the Citrus sinensis surfactant had an early breakthrough at 28 seconds with 73.68% oil recovery, compared to the 4000 ppm dosage, which had a breakthrough at 34 seconds with 77.5% oil recovery. The Carica papaya surfactant at a 2000 ppm dosage had a breakthrough at 33 seconds with an oil recovery of 85%, and at 39 seconds with an 80.95% recovery for the 4000 ppm dosage. The Garcinia kola surfactant had a late breakthrough at 44 seconds with 76.08% oil recovery for the 2000 ppm dosage and 80.00% recovery at 40 seconds breakthrough for the 4000 ppm dosage. The Carica papaya surfactant provided the highest oil recovery at the lowest dosage of 2000 ppm.