The effect of aluminosilicate in anionic–nonionic surfactant mixture on wetness and interfacial tension in its application for enhanced oil recovery

In particular, this study aims to investigate the effect of aluminosilicate nanoparticle in the mixture of anionic (Sulfonated Alkyl Ester) and nonionic (Fatty Ester Oleate) surfactants on the interfacial tension and wettability related to EOR processes. Various experiments were conducted such as measuring interfacial tension between oil and brine using spinning drop tensiometer, measuring contact angle between surfactant-NPs-brine solution and Buff Berea core using optical tensiometer, conducting spontaneous imbibition, and core flooding tests. It is observed that the more anionic surfactant in the mixture the more significant aluminosilicate reduces contact angle and increases interfacial tension (IFT), which promotes contradicting effect on oil recovery. In this study, the IFT prevails and eventually reduces ultimate oil recovery. At spontaneous imbibition tests the ultimate oil recovery is decreased from 58% to 47% and from 63% to 46% for SAE-01A and SAE-01B, respectively. The ultimate oil recovery is reduced from 54% to 35% and from 50% to 39% at core flooding tests (Figure 16) for SAE-01A and SAE-01B, respectively. The aluminosilicate nanoparticle contributes positively as the ratio of SAE and FEO becomes smaller. At surfactant formulation ratio of 1:2 (SAE-01C), the IFT is decreased slightly from 4.36 x 10⁻³ mN/m to 2.36 x 10⁻³ mN/m and contact angle is also slightly reduced from 41.9° to 40.3° by adding 250 ppm NPs. The results show that ultimate oil recovery is increased 52% to 61% and from 47% to 49% at spontaneous imbibition tests and core flooding tests, respectively.