Research subject: In recent decades, water and gas injection have gained significant attention for enhancing oil recovery. However, some engineers believe that alternative methods can play a more pivotal role in this field. The use of surfactants is considered an innovative technique that has had a notable impact on the oil industry. Nevertheless, the large-scale production of such materials is financially costly. Additionally, their synthesis results in the generation of toxic and hazardous waste, posing various threats to human health and the environment, ultimately leading to widespread and irreparable pollution. The use of natural surfactants has emerged as a viable solution with relatively high efficiency. These natural surfactants are extracted from the leaves of native plants, offering a cost-effective approach. Moreover, they are biodegradable and pose no risks to human health or the environment.
Research approach: The combination of these natural surfactants in oil-related experiments has yielded satisfactory results, demonstrating their effectiveness in reducing interfacial tension between water and oil, as well as modifying the viscosity of crude oil. This study specifically examined the interaction between surfactants and divalent ions at their lowest concentrations. One of the testing processes involved injecting these solutions into a micromodel, which was subsequently analyzed.
Main results: The combination of these surfactants with divalent ions and crude oil significantly reduced interfacial tension. Notably, the combination of Morus leaf extract with calcium ions reduced the interfacial tension of crude oil to 15.6 mN/m, while Citrus extract with sulfate ions reduced it to 13.6 mN/m. Additionally, in many viscosity tests, a reduction in crude oil viscosity was observed. The combination of calcium ions with Morus extract resulted in approximately 41% oil recovery, whereas sulfate ions with Citrus extract led to a 50% final recovery rate.