Study On The Water Separation And Oil-Water Interfacial Properties Of Base Oil For Marine Oil

Base oil accounts for the vast majority in lubricant, base oils that from different origin and process have various structure and property as well as sensitivity for additive, and it’s oil-water emulsion stability is also diverse. So it is necessary to findg the main factors affecting the emulsion stability and study the effect of additive on the water separation property and research the mechanism of oil-water separation.Firstly, column chromatography,element analysis, IR, NMR and other analytical ways were used to the studied the base oil’s property and the structure; Secondly, the oil-water separation property of different base oils and the effect of complex additive on the oil-water separation property as well as the effect of different additives on the oil-water separation property were studied; Thirdly, the effect of different combination base oils on the key performance of marine lubricanting oil was studied; At last, interfacial tension and the interfacial shear viscosity as well as the particle diameter of emulsion were used to research the mechanism of oil-water separation.The results show that the viscosity and the composition and structure are the most important effect factors on the oil-water separation properties. It is found that the greater the viscosity and the more aromatics as well as resins of the base oil, the poorer the anti-emulsification and water separation property. In the all base oils t, the water separation abilities because worse in order of hydrogenated base oil, solvent refining base oil, heavy constituent base oil. In the item of the influence on different combinations of base oils on the key characters of marine lubricant, Ji Nan HⅥⅡ-10 and Mao Ming HⅥ750 is better than any others. It has shown that the water-separation properties is best when only adding 3% succinamide dispersant or only adding 3% salicylate detergent or only adding 1% sulfonate detergent or only adding 1.2% alkylphenols detergent or only adding 1.2% zinc alkaline antioxidant, but naphthenates detergents nearly has no effect on water-separation properties. In the all base oils that were studied, the oil-water interfacial tension becomes lower in order of hydrogenated base oil, solvent refining base oil, heavy constituent base oil, the oil-water interfacial shear viscosity rise and the initial particle diameter fall in the same order. The additive reduces the interfacial tension and the initial particle diameter of the emulsion, increases interfacial shear viscosity of the system, resulting in poorer water separation.