SYNTHESIS OF FLUORESCENT SILICA NANOPARTICLES TO THEIR QUANTIFICATION IN EOR APPLICATIONS

Silica nanoparticles (SiNPs) display advantages compared to other NPs, and their applications in enhanced oil recovery (EOR) have significantly increased in recent years.1 However, changes in their colloidal stability might cause aggregation and retention into porous media, estimating the losses is crucial for designing field applications of these NPs. In this work, three fluorescent SiNPs with different morphology (see Figure 1) were synthesized and characterized. DLS and ζ-potential measurements show that fluorescent SiNPs have similar colloidal stability to the commercial SiNPs. Once analyzing the emission spectra over time, it was noticed that after 1 hour and 30 minutes, all of the NPs maintained a steady intensity value. However, (2) exhibits greater stability and intensity. The same test was conducted using sodium dodecyl sulfate (SDS) at 0.1 wt%, and the findings reveal that (2) is stable since beginning. To quantify, the NPs (2) was selected and the analytical performance characteristics were studied. Fluorescent SiNPs with similar colloidal behaviour to SiNPs commercial were designed and synthetized, and through fluorescence the quantification for sample (2) was possible showing high sensitivity and selectivity.