Synthesis And Emulsifying Properties Of Sulfonate Type Polymer Surfactants

In polymer flooding process, the water-soluble polymers are added to increase water phase viscosity, reduce the water phase permeability, improve water-oil mobility ratio and sweep efficiency, at last to improve oil recovery. And polymer flooding is suitable for crude oil viscosity that is generally not more than 100 mPa·s. Higher viscosity of crude oil, higher polymer concentration is required to achieve proper mobility control. However, it will increase the cost and reduce the economic benefit. Besides, polymer cannot emulsify the crude oil, especially when oil viscosity is higher. As a result, water-oil mobility ratio cannot be improved and improving oil recovery is limited. Therefore, the focus of chemical flooding to enhance oil recovery has always been to develop new chemical flooding agents.To improve the disadvantage that polymer cannot emulsify the crude oil, this paper synthesised a kind of polymeric surfactant to emulsify crude oil and hydrocarbons. The amphiphilic structure is introduced into the molecular chain of the polymeric surfactant, mainly used in oil field. The polymeric surfactants can increase the water phase viscosity and reduce the water phase permeability. And the polymeric surfactants can also emulsify crude oil, reduce oil viscosity and increase oil phase permeability. Through the double effects on water and oil phase, it can reduce the water-oil mobility ratio. Thus, the polymeric surfactant has significant application in enhanceing oil recovery.Firstly, the surface active monomer, abbreviated as surfmer, AA-EO25C12 was synthesized. The polymeric surfactant, denoted by DEA, was synthesized with the surfmer and AMPS (2-acrylamide-2-methyl propane sulfonic acid). And the surfmer and DEA were characterized by the methods of FT-IR and 1H-NMR. Besides, PAMPS was also synthesized under the same condition as DEA for a reference.By methods of intrinsic viscosity, intrinsic viscosity of DEAs is lower than that of the PAMPS. Less the surfmer, the intrinsic viscosity is higher. By introducing appropriate amount of surfmer, DEAs can associate to form a three-dimensional network structure. DEAs shows viscosity increasing both in distilled water and salt solution and its temperature resistance is superior to PAMPS. And the DEAs show the characteristics of pseudoplastic fluid and viscoelastic behavior in distilled water and NaCl solution. DEAs can reduce the surface/interface tension to a certain extent, have emulsifying ability and can form stable O/W type emulsion with diesel. Besides, DEAs can also emulsify and reduce viscosity of heavy oil. When DEA-0.5 concentration is 3000 mg/L, the viscosity reduction is 96.83%. Adding salt, the ability of emulsifying and viscosity reducing of DEAs is weakened. When DEAs is compounded with surfactant, the ability of emulsifying and viscosity reducing of DEAs can be improves by adding suitable amount of surfactant. But for different types of surfactants, degree of improvement is different, OP-10> SDBS> BS-12.