Synthesis And Application Study Of Amphoteric Surfactant For Heavy Oil Chemical Flood

Nonylphenol polyoxypropylene ether sulfate(NPPS) was synthesized,and the dynamic interfacial tension between Zhuangxi crude oil and brine containingthe surfactant was studied. It is found that ultra-low interfacial tension can not achieve with NPPS or Na₂CO₃ along.But the mixing systems of the surfactant and Na₂CO₃ exhibit synergism and the interfacial tension could reach 10^-4mN/m at low alkaline concentration(0.35%) and low surfactant concentration (0.0025%).It is also found that the mixing systems of the surfactant and amine exhibit synergism when mass fraction of amine is above 0.05%and mass fraction of NPPS is under 0.05%.Four dinonylphenol polyoxypropylene ether sulfonates(DNPPS) and one dinonylphenol polyoxyethylene ether sulfonate(DNPES) was synthesized and the interfacial tensions between surfactant solution with different salinity and Zhuangxi crude oil were examined. DNPPS-C has the best performance and the interfacial tension with 6.5%NaCl reachs 3.28×10^-4 mN/m.Dynamic interfacial tensions with mixture of DNPPS-C and Na₂CO₃ were meatured.Synergism was found in the mixtures of 0.005%～0.01%DNPPS-C and 0.1%～1.0%Na₂CO₃ and the interf(?)ial tension reach a value lower than 10^-4 mN/m.The interfacial tension with mixtures of 0.01%～0.1%MA and 0.005%～0.05%DNPPS or with mixtures of 0.05%～0.1%TMA or TEA and 0.005%DNPPS reach 10^-3 mN/m or lower.Synthesizing octylphenol polyoxyethylene sulfonate olefine-addition method were studied.The yiel(?)l of intermediate product were meatured by chloride ion titration and HPLC. Results indicate that the optimum temperature of sodium treatment is 80℃and the optimum temperature of allylating is 60℃.At optimum reaction temperature,the total yield of allyl octylphenol ethoxylates meatured by titration and HPLC is 85.19%and 83.07%,respectively.