Study On Interfacial Tension Between Aqueous Nonyphenol Polyoxyethylene Ether Surfactants Solutions And Crude Oil And Its Composition

It was presented in this paper that a series of gemini nonylphenol polyoxyethylene ether (GNP) and monomer nonionic surfactant of nonylphenol polyoxyethylene ether (NP) were synthesized in laboratory, and the interfacial tension between surfactant solutions and crude oil as well as its composition(gasoline, kerosene, light diesel oil, heavy diesel oil, first decompression line oil, second decompression line oil, third decompression line oil) was measured by using a spinning drop tensiometer under the temperature from 25℃to 50℃and the pH value from 5 to 9.The experimental results showed that the array mode of GNP molecules at the oil-water interface was closer than that of NP molecules as their oxygen ethylene groups amounts and HLB values approximately equal to each other. The size order of reducing interfacial tension was taken following as:crude oil> first decompression line oil, second decompression line oil, third decompression line oil> kerosene, light diesel oil, heavy diesel oil> gasoline. Within the temperatures from 25℃to 50℃, the interfacial tension between surfactants solutions and oil was decreased with temperature elevation and pH values increase, and the interfacial tension was increased along with oxygen ethylene groups adding of the GNP and NP surfactants.