Contact Angle And Interfacial Tension Studies of Some Hydrocarbon-Water-Solid Systems

Abstract

Abstract An apparatus was built to measure interfacial tensions and contact angles of hydrocarbon-water-solid s:rstems at variable temperatures and atmospheric pressure. Interfacial tensions were measured for benzene, n-dodecane, Klearol and nitrogen against water over a temperature range of 25 to 90 °C. For the n-dodecane-water system, a water-soluble cationic surfactant, a water-soluble nonionic surfactant and an oil-soluble carboxylic acid were added. Relationships among interfacial tension, temperature, surfactant concentration and interface age were determined.Contact angle measurements were made primarily for the n-dodecane-water system on flat quartz and calcite crystal surfaces. An oil-soluble amine, a carboxylic acid, and water-soluble anionic, cationic and nonionic surfactants were used as additives. Without the surfactants, the carefully cleaned solids were completely water-wet. Finite contact angles resulted from contamination or the addition of certain of the surface-active compounds, and were generally accompanied by hysteresis. The magnitude of the contact angles indicates the orientation and degree of packing of surface-active molecules at solid-liquid interfaces, and points out the role of surface charge and polarity in adsorption.IntroductionIN CANADA AND THE UNITED STATES, approximately 90 per cent of all the oil produced through the application of enhanced recovery processes is obtained bywaterflooding. The rising cost of exploring for new oil, co