Study On The Synthesis And Application Of The Petroleum Sulfonates

The Petroleum Sulfonate (PS) is an efficient surfactant in EOR (Enhanced Oil Recovery). It can easily reduce the interfacial tention in the circumstance of crude oil and water. The composition of raw material is complex, thus the composition and structure of petroleum sulfonate is complex. The surfactant for EOR should have the properties of low interfacial tension (IFT) and low adsorption, so it can increase the efficiency oil-displacement. As a result, making one kind of petroleum sulfonate with high interfacial activity and low adsorptive loss is of great significance.In this paper, one kind of PS was synthesized in a falling-film sulfonation reactor by the raw material of Suizhong low solidication point naphthene-base vacuum gas oil (VGO) and SO₃ as sulfanation agent. Through comparing the properties of several kinds of oils, two kinds of oils were selected as the materials to synthesize PS by using the falling-film reactor. The conditions of synthesization were optimized by doing lots of experiments.The mass transfer property of the reactor was studied by using the material of vacuum gas oil. The criterion formula of gas film mass transfer of the reactor was studied by the ways of doing some experiments and calculations. So it also testified that the mass transfer of the reactor was controlled by gas film diffusion. Then the influences of the sulfonational rate by the structural and operational parameters of the reactor were studied.The composition and molecular mass of the products were analysized and determined by the ways of infrared spectrometry, two-phase titration method and ESI-MS. Then the validity of the reaction was approved. During the research, it also found that the average relative molecular mass was appropriate and its average relative molecular mass distributes within a broad range, so it confirmed that the PS was fitted for EOR as oil-displacement surfactant. The molecular structure of the product of sulfonation was analysized by the ways of elemental analysis and NMR.During the study on the property in application of the products, some compounds which were mixed by the products of PS and other kinds of surfactants were used in the system of Shengli oil and stratum water. By comparing the values of interfacial tension of those compounds, the best compound which could make the value to ultralow (≤0.001mN·m^-1) was found. Some experiments were also done in the research to test the chosed-compound's oil-displacement efficiency by using the core of rock. The experiments were done to make sure the chosed-compound to fullfil the demands of EOR in locations.