Investigation on interfacial/surface properties of bio-based surfactant N -aliphatic amide- N , N -diethoxypropylsulfonate sodium as an oil displacement agent regenerated from waste cooking oil

Development of Bio-Nanofluids Based on the Effect of Nanoparticles' Chemical Nature and Novel Solanum torvum Extract for Chemical Enhanced Oil Recovery (CEOR) Processes

This study aimed to develop novel bio-nanofluids using Solanum torvum extracts in synergy with nanoparticles of different chemical nature as a proposal sustainable for enhanced oil recovery (EOR) applications. For this, saponin-rich extracts (SRE) were obtained from Solanum torvum fruit using ultrasound-assisted and Soxhlet extraction. The results revealed that Soxhlet is more efficient for obtaining SRE from Solanum torvum and that degreasing does not generate additional yields. SRE was characterized by Fourier transformed infrared spectrophotometry, thermogravimetric analysis, hydrophilic-lipophilic balance, and critical micelle concentration analyses. Bio-nanofluids based on SiO2 (strong acid), ZrO2 (acid), Al2O3 (neutral), and MgO (basic) nanoparticles and SRE were designed to evaluate the effect of the chemical nature of the nanoparticles on the SRE performance. The results show that 100 mg L-1 MgO nanoparticles improved the interfacial tension up to 57% and the capillary number increased by two orders of magnitude using this bio-nanofluid. SRE solutions enhanced with MgO recovered about 21% more than the system in the absence of nanoparticles. The addition of MgO nanoparticles did not cause a loss of injectivity. This is the first study on the surface-active properties of Solanum torvum enhanced with nanomaterials as an environmentally friendly EOR process.

Interfacial Properties, Wettability Alteration and Emulsification Properties of an Organic Alkali-Surface Active Ionic Liquid System: Implications for Enhanced Oil Recovery

Combinatory flooding techniques evolved over the years to mitigate various limitations associated with unitary flooding techniques and to enhance their performance as well. This study investigates the potential of a combination of 1-hexadecyl-3-methyl imidazolium bromide (C₁₆mimBr) and monoethanolamine (ETA) as an alkali–surfactant (AS) formulation for enhanced oil recovery. The study is conducted comparative to a conventional combination of cetyltrimethylammonium bromide (CTAB) and sodium metaborate (NaBO₂). The study confirmed that C₁₆mimBr and CTAB have similar aggregation behaviors and surface activities. The ETA–C₁₆mimBr system proved to be compatible with brine containing an appreciable concentration of divalent cations. Studies on interfacial properties showed that the ETA–C₁₆mimBr system exhibited an improved IFT reduction capability better than the NaBO₂–CTAB system, attaining an ultra-low IFT of 7.6 × 10⁻³ mN/m. The IFT reduction performance of the ETA–C₁₆mimBr system was improved in the presence of salt, attaining an ultra-low IFT of 2.3 × 10⁻³ mN/m. The system also maintained an ultra-low IFT even in high salinity conditions of 15 wt% NaCl concentration. Synergism was evident for the ETA–C₁₆mimBr system also in altering the carbonate rock surface, while the wetting power of CTAB was not improved by the addition of NaBO₂. Both the ETA–C₁₆mimBr and NaBO₂–CTAB systems proved to form stable emulsions even at elevated temperatures. This study, therefore, reveals that a combination of surface-active ionic liquid and organic alkali has excellent potential in enhancing the oil recovery in carbonate reservoirs at high salinity, high-temperature conditions in carbonate formations.