Study On Synthesis And Oil Displacement Performance Of Reactive Sulfonate Gemini Surfactant

Gemini surfactants have more remarkable performance in reducing surface tension and oil/water interfacial tension than their corresponding monomer surfactants,so they have attracted great attention in the field of tertiary oil recovery.In this thesis,maleic anhydride,fatty alcohols and chlorinated olefins are used as the main raw materials,through conventional organic reactions,a series of sulfonate-type 1 Gemini surfactants containing reactive groups have been synthesized,purified and characterized.The changes of surface properties and interface properties of aqueous solution were investigated.The main research contents and results are as follows:(1)Maleic anhydride,fatty alcohol(n=8,10,12,14,16)and 3,4-dichloro-1-butene were used as the main reactants,a reactive sulfonate Gemini surfactant containing an alkenyl reactive group were prepared by a three-step reaction(GS-AG-n(n=8,10,12,14,16)),and the structure of the final product after purification were characterized by FT-IR and 1H NMR.The surface tension of GS-AG-n aqueous solution were measured,the results showed that critical micelle concentration(CMC)was 1.55×10-2 mol/L when the carbon chain length of GS-AG-n was n=8.When the carbon chain length of GS-AG-n was n=16,the CMC was 2.14×10-4 mol/L.GS-AG-16 has good foam stability.The emulsification performance test showed that GS-AG-n has better emulsification performance,and the emulsion of GS-AG-12 was the most stable.The particle size test results showed that the average particle size of GS-Ag-16 is the largest,which is 399.1 nm,and the particle size dispersion coefficient also increased.The wettability test results showed that with the increase of time,the contact Angle of GS-AG-n decreased first and then tends to be stable,and the wettability of GS-AG-12 on PTFE surface was the best,and the adsorption equilibrium value was 64.2°.GS-AG-16 showed the best effect in reducing the interfacial tension between oil and water,and the interfacial tension can reach 1.23×10-2 mN/m.(2)Maleic anhydride,fatty alcohol(n=8,10,12,14,16),diethanolamine and acryloyl chloride were used as the main reactants,reactive sulfonate Gemini surfactants containing amide groups were prepared by a series of reactions(GS-AM-n(n=8,10,12,14,16)),and the structure of the final product after purification was characterized by FT-IR and 1H NMR.The surface tension of GS-AM-n aqueous solution was measured,and the results showed that when the length of hydrophobic carbon chain was 16,the CMC at room temperature was 6.83×10-5 mol/L.The foam performance of GS-AM-n were measured by volumetric method,and the results showed that GS-AM-16 has good foam stability.The emulsification performance test results showed that GS-AM-n has good emulsification performance,and GS-AM-14 has the best emulsification performance,which can form a uniform and stable emulsification system.The results showed that with the increase of hydrophobic chain length,The average particle size of GS-AM-n increases continuously,and the distribution range of particle size becomes wider.The wettability results showed that the contact angle of GS-AM-14 was the minimum of 53.6°,and the wettability was the best.The oil/water interfacial tension of GS-AM-16 was 6.82×10-3 mN/m.(3)The products were prepared in the laboratory through three steps of single esterification,double esterification and sulfonation.The traditional non-ionic surfactant lauryl alcohol polyoxyethylene ether(AEO-9)was mixed with new reactive sulfonate Gemini surfactants GS-AG-n and GS-AM-n,respectively.The interfacial tension of GS-AG-n/AEO-9 and GS-AM-n/AEO-9 were tested respectively,and the optimal mixing ratio was determined and the emulsification performance was studied,the mixed system suitable for simulated displacement experiment was determined.The experimental results showed that the interfacial activity and emulsifying ability of GS-AG-n/AEO-9 and GS-AM-n/AEO-9 are better than those of any surfactant alone.The results of the displacement experiment showed that when the mass concentration of the oil displacement agent system was 0.3%,the ability to emulsify and disperse crude oil was the best,and the oil displacement efficiency was the highest.When the mass concentration of the oil displacement agent system was 0.3%,the results of displacement experiments on the compound oil displacement agent systems 1?6 showed that the surfactant flooding stage can increase oil recovery by 7.45%,10.75%,17.54%,11.47%,15.26%and 22.61%,respectively.The final recovery factors were 45.93%,48.43%,56.27%,50.12%,54.42%and 61.35%.The results showed that it is of great scientific and industrial significance to design a new type of reactive sulfonate Gemini surfactant and study its performance for enhancing oil recovery.