Experimental investigation of the inhibitory behavior of metal oxides nanoparticles on asphaltene precipitation

Asphaltene deposition is one of the problematic aspect of petroleum industry, which imposes serious operational damage and cost. Adhering to reservoir rocks and consequently obstruction of their pores, blockage of pipelines, and make fouling in process equipment such as pumps is part of serious difficulties which are occurred by deposition of asphaltene. Many investigations have been performed to inhibit asphaltene deposition using inhibitors, which not only show high efficiency in suppressing asphaltene precipitation but also they are compatible with the environment. In accordance to this purpose, in this research, the effect of Fe3O4, NiO and gamma-Al2O3 metal oxide nanoparticles was experimentally investigated on the synthetic oil in order to mitigate the risk associated with asphaltene deposition and postpone the onset of asphaltene precipitation. It was concluded that the aforementioned metal oxide nanoparticles were effective on suppressing the onset point and reducing the amount of precipitated asphaltene. The best results were obtained for gamma-Al2O3 nanoparticles with 0.1 wt.% which it was attributed to its acidity chemical nature as well as high ratio of specific surface area. The NiO metal oxide nanoparticles exhibited a good operation though not to the same extent as gamma-Al2O3. The poor results were related to Fe3O4 metal oxide nanoparticles with 0.01 wt.%. It was concluded that the metal oxide nanoparticles with more Bronsted acid sites in their structures were more capable to have a polar interaction with asphaltenes and consequently could suppress the precipitation process.