Study On DIFT Of Nano-SiO₂ Modified By KH-792 In EOR

Surfactant is a series of flexible and versatile fine chemical products and gradually becomes the hot research topic because of its'practical application and the physical chemistry actions, such as wetting or anti-adhesive, emulsion or demulsification, foaming and solubility, dispersion, washing, anti-corrosion, antistatic property. The surfactant separately employed in EOR area has been more of the application. However, the research on reducing the oil-water interfacial tension by the mixture of surfactant and modified nano-materials is seldom reported. The primary object of this dissertation is to reduce the interfacial tension between oil and solution to ultralow using the mixture of SLPS-45 and the nano-SiO2 modified by the synthetic material which is that grafted on the KH-792 side chain by acetyl chloride.The product was synthesized by introducing an acetyl group into the silane coupling agent with amine as the feed stock in this novel. The molecular structure of the modified materials were characterized and confirmed by FT-IR, SEM and TEM, and the compound obtained was final objective product.The article provides a new method for changing nano-particles size by using supersonic method to optimize the conventional preparation of nanometer SiO2.The result obtained showes that the nano-SiO2 size prepared by ultrasonic is smaller and the product occurs as spherical particles and has less agglomerate by adding a little of inorganic salt electrolyte and surfactant. The interfacial properties of the mixture which is SLPS-45 and nano-SiO2 modified by KH-792 and acetyl chloride when be used in the oil-water system of T1, T4, T6 and Sheng2-0 is investigated by measuring the interfacial tension. It is showed that the compound can lower the oil-water interfacial tension from 10-3 mN/m to 10-2 mN/m. The compound system shows good synergistic effect and the optimum condition is that the ratio of the modified surfactant to SLPS-45 is 0.1% to 0.3%.