Synthesis And Performance Study Of Bisphenyl Sulfonate Gemini Surfactant

Compared to other Gemini surfactants,anionic Gemini surfactants are more suitable for high salinity,high temperature and other special reservoirs to enhanced oil recovery,and it can reduce the interfacial tension effectively in small concentrations.Wide aromatic compound sources,low price,with multiple active sites,aromatic ring is easy to introduce hydrophilic groups and generate a variety of compounds;furthermore,surfactant molecules can be easier formed adsorption in the oil/water interface with the characteristics of weak polarity and easy polarization of aromatic ring.Therefore,series sulfonate Gemini surfactants were designed and synthesized by used double diphenyl as the skelecton of the spacer group.In this paper,a series(five kinds)bis-phenyl-sulfonate gemini surfactants(BPSGS)were synthesized of salicylaldehyde,1,2-dibromoethane,N-alkanes bromine(the number of carbon atom are 8?10?12?14?16 respectively)and chlorine acid through multi-step reaction.In an example of the C14,through the means of single factor and orthogonal analysis,the synthesis steps had been optimized and the optimum reaction conditions had been confirmed.Intermediates and products were isolated and purified and their structural had been characterized by IR,1H-NMR,the results showed that structure consistent with the desired product product.The surface properties of the new series of Gemini surfactants were studied,their critical micelle concentrations were lower than traditional surfactants about two orders of magnitude,low surface tension could reach 26.5 mN/m,excellent surface activity was exhibited.pC20 value and cmc/C20 ratio comparison biphenyl sulfonate Gemini surfactant with conventional surfactants,biphenyl sulfonate Gemini surfactant molecules tend to adsorb on the surface of the solution more easily,lowing the surface tension with a higher efficiency.The researches of series of biphenyl sulfonate Gemini surfactants on the impact of oil-water interfacial tension showed that it can reduce the interfacial tension between oil and water to less than 5 × 10-3mN/m.With the increase of surfactant concentration the interfacial tension gradually decreased and then increased,and finally reached steady state,optimal concentration appeared;over time the interfacial tension decreased and then increased,and finally stabilized,there a minimum,and the concentration the higher the minimum of the interfacial tension appear the sooner;moreover,biphenyl sulfonate Gemini surfactants were able to maintain a lower ratio interfacial tension than conventional surfactants in a high concentration(>6%)and a wide concentration(range 0.7%to 6%),and has a high resistance to Ca2+ capacity.When studied the properties of the foam,wetting,adsorption and other aspects of its application,the difference in performance between different hydrophobic carbon chain length Gemini surfactant,and compared to traditional surfactants,biphenyl sulfonate Gemini surfactant exhibited a more superior performance.