| Literature DB >> 29292747 |
Keliang Wang1, Gang Wang2, Chunjing Lu3, Cuiying Pei4, Ying Wang5.
Abstract
Amphiphilic nanoparticles have attracted increasing interest as Pickering emulsifiers owing to the combined advantages of both traditional surfactants and homogeneous particles. Here, foaming amphiphilic fluorinated nanoparticles were prepared for enhanced oil recovery by the toposelective surface modification method. The structure and properties of amphiphilic nanoparticles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, a laser diffraction method, fluorescence microscopy, a pendant drop tensiometer, and foamscan. It was found that the amphiphilic fluorinated nanoparticles exhibited significant interfacial activity at the air-water interface and generated stabilized aqueous foams against coalescence and drainage even in the absence of surfactants. When the particle concentration reached 0.6 wt %, the adsorption of the amphiphilic nanoparticles at the interface was saturated and the equilibrium surface tension dropped to around 32.7 mN/m. When the particle concentration reached 0.4 wt %, the Gibbs stability criterion was fulfilled. The amphiphilic nanoparticles foam system has a better plugging capacity and enhanced oil recovery capacity. The results obtained provide fundamental insights into the understanding of the self-assembly behavior and foam properties of amphiphilic fluorinated nanoparticles and further demonstrate the future potential of the amphiphilic nanoparticles used as colloid surfactants for enhanced oil recovery applications.Entities:
Keywords: amphiphilic nanoparticles; anisotropy; colloid surfactants; enhanced oil recovery
Year: 2017 PMID: 29292747 PMCID: PMC5744338 DOI: 10.3390/ma10121403
Source DB: PubMed Journal: Materials (Basel) ISSN: 1996-1944 Impact factor: 3.623
Figure 1Synthesis scheme of the fluorescent Janus particles by the Pickering emulsion approaches.
Composition of four foam systems.
| Foam Systems | Composition |
|---|---|
| traditional surfactants | 0.4 wt % CAB |
| homogeneous modified particles | 0.4 wt % H30 |
| mixtures of particles and surfactants | 0.3 wt % DDAB + 0.1 wt % T30 |
| amphiphilic fluorinated nanoparticles | 0.4 wt % amphiphilic nanoparticles |
Figure 2Schematic diagram of (a) the single Berea core flooding experiments and (b) the parallel Berea core flooding experiments.
Figure 3Fourier transform infrared (FTIR) spectra of silica particles.
Figure 4SEM images of the wax colloidosomes stabilized by (a) the bare silica and (b) the APTES-silica. The insets show the size distribution of the silica particles.
Figure 5Fluorescence images of the fluorinated silica Janus particles with fluorescein isothiocyanate (FITC).
Figure 6The interfacial properties of the amphiphilic fluorinated nanoparticles at various concentrations: (a) Dynamic surface tension; (b) Variation of E with the surface tension ϒ. The solid line shows E = ϒ/2 (Gibbs stability criterion).
Figure 7(a) Foam stability and (b) Liquid foam fraction of the amphiphilic fluorinated nanoparticles at various concentrations.
Figure 8Plugging capacity of four foam systems at (a) 40 °C and (b) 80 °C.
Oil recovery capacity of the foam systems.
| Injection Mode | Sand Pack | K (μm2) | Oil Saturation | Oil Recovery before Injection of Foam | Oil Recovery after Injection of Foam | Enhanced Oil Recovery | ||
|---|---|---|---|---|---|---|---|---|
| Respectively | Total | Respectively | Total | |||||
| surfactants | high | 0.615 | 72.6% | 48.3% | 34.7% | 4.9% | 45.8% | 11.1% |
| low | 0.044 | 73.8% | 21.2% | 17.3% | ||||
| homogeneous particles | high | 0.624 | 71.9% | 47.6% | 35.3% | 11.0% | 56.5% | 21.2% |
| low | 0.046 | 73.1% | 22.9% | 31.4% | ||||
| mixtures of particles and surfactants | high | 0.591 | 71.9% | 47.8% | 34.5% | 9.9% | 49.8% | 15.4% |
| low | 0.044 | 72.5% | 21.1% | 20.9% | ||||
| amphiphilic particles | high | 0.607 | 71.4% | 48.6% | 34.9% | 16.3% | 67.8% | 32.9% |
| low | 0.045 | 73.4% | 21.2% | 49.4% | ||||