Enhanced oil recovery using hyperbranched polyglycerol polymer-coated silica nanoparticles

Functionalized Fe3O4-SiO2 magnetic nanoparticles (Fe-Si-MNPs) coated with hyperbranched polyglycerol polymer were prepared and tested for oil recovery from oil in water (O/W) emulsions. The structure, chemistry, and surface modifications of the newly developed demulsifier (PSiMNPs) were analyzed, and the percentage demulsification efficiency (%eta(dem)) was tested at differing concentrations of surfactant (C-sur), oil (C-oil), and demulsifier (D-PSiMNPs). The developed PSiMNPs can be separated from the solution by a magnetic field, regenerated using ethanol, and reused several times. The reported %(eta dem) was >= 80% for all the studied C-oil. The %eta(dem) improved as the C-sur and pH decreased, with maximum values of 98.8% and 98.5% achieved at C-sur = 0.05 g/L and a pH = 4, respectively. A D-PSiMNPs = 100 mg/L was sufficient to achieve %eta(dem) of 99.4% for C-oil =100 mg/L and slightly decreased to-93% for C-oil-4000 mg/L. The PSiMNPs can be reused up to 15 times with a steady %eta(dem) of 89.1% for C-oil = 100 mg/L and 88.6% for C-oil = 4000 mg/L. The adsorption of oil on the PSiMNPs follows Freundlich isotherm with maximum adsorption capacity (qmax) of 192.8 g/mg and Langmuir constant (b) of 28.06 mg/L for C-oil = 900 mg/L. The q(max) of the recycled PSiMNPs slightly decreased to 189.08 g/mg. The kinetic of oil recovery follows the PSO with a K-2 of 0.0169 g/mg. min. Surface modification of Fe-Si-MNPs enhanced the oil adsorption, increased the adsorption capacity, and extended the service life resulting in a better cost and process feasibility.

Automated summary

Functionalized Fe3O4-SiO2 magnetic nanoparticles coated with hyperbranched polyglycerol polymer were developed for oil recovery from oil in water emulsions. The newly developed demulsifier PSiMNPs showed high efficiency in demulsification and can be reused multiple times. The surface modification of PSiMNPs enhanced oil adsorption, increased adsorption capacity, and extended service life, resulting in improved cost and process feasibility for oil recovery applications.