Synthesis And Properties Of Oil-displaced Anionic Gemini Surfactants

A new-style surfactant-Gemini was synthesized in this paper. Due to its low-costand high-powered, it can be applied to resolve oil-displacement problem, and a newsynthesis route was introduced. In this experiment, product structures,influenced-yield factors, technoligical conditions, product surface and interfaceproperties and other applied properties and so on were investigated. Compared withother synthesized Gemini surfactants, analytical results and methods can be used asways and means to estimate oil-displacement capacity of Gemini surfactants infollowing experiment.The overall results as following:1. Nonylphenol and formaldehyde were used as raw material and chlorosulfuric acidused as sulfonation reagent, by fiber-bridge and then sulfonation reaction, anew-type anionic Gemini surfactant was synthesized. Optimum sulfonationtechnics conditions were obtained by orthogonal experiment: T=70℃, t=2.5h,chlorosulfuric acid versus nonylphenol=1.2:1(mol).2. CMC,γcmc and C₂₀ of Gemini surfactants were studied and it was found that theGemini surfactants were about one order of magnitude more efficient at formingmicelles(CMC) than conventional surfactants. For γcmc only, Gemini surfactantsdidn't show great advantages over conventional monomeric ones, but it wasknowed from C20 that they were more efficient in declining surface tension ofwater.3. Interface properties of Gemini surfactants including the capability ofsolubilization, emulsification, wetting and rheological property were also studied.At the same concentrations of 1.0mol/L, the solubilization capability of Gemini-Ato benzene was 7.0g, but Gemini-N was 8.1g. It indicated that Gemini surfactantswere superior to traditional ones;with the increase of concentration, the capabilityof emulsification of Gemini-N increased. When 1-dodecanol was added, longertime of water separated was necessary and maximum emulsification capabilitywas reached under the low surfactant concentration;The contact angles on glass ofGemini-A surfactant solution were decreased with the concentration increased, butGemini-N changed little. It indicated that capability of Gemini-N was better thanGemini-A. In addition, rheological property of Gemini-N was studied. It wasfound that apparent viscosity of Gemini-N was increased with the concentrationincreased and decreased with the temperature and time increased.4. The applied properties of Gemini including temperature resistance, alkaliresistance, and hard-water resistance were investigated. It was found that theGemini surfactants had better alkali resistance capability, which measured up GBstandards;Gemini surfactants decomposed little when they were heated to 180℃;However, hard-water resistance of Gemini was ordinary, but it can be improvedwith NaCl or OP-10 added.