Research On The Synthesis, Properties And Application Of Disodium Alkyl Diphenyl Ether Disulfonate

Alkyl diphenyl ether disulfonate(ADPODS) is a serie of anionic surfactants with many functions.It has two hydrophilic head groups and different from conventional surfactants.ADPODS showes very good surface physical and chemical properties and application properties.In this paper,ADPODS surfactants(C₁₂-MADS,C₁₂-DADS) were synthesized by the experimental condition.Their surfactivity were studied.Adsorption on kalion and interfacial tension were determined as well,while the oil/water interfacial tension of C₁₂-DADS system can be reduced to 3.01×10^-3mN/m.The main results are as follows:1 The alkyated diphenyl ether disulfonate were made byα-alkene,diphenyl and chloric sulfoacid.The synthetic technique conditions of alkylation and sulfonation were optimized.The synthetic samples were characterized by HPLC/MS.Alkylation was carried out with n(α-alkene):n(diphenyl)=1.0:1.0 at 70℃for 4h to attain 88% yield.Sulfonation with n(alkylated diphenyl):n(chloric sulfoacid)=1:5 was carried out at 10℃for 20min,and average number of sulfonic acid group per molecule was 1.86.2 Surface chemical properties of ADPODS were determined.ADPODS posses stable Surface chemical properties when dissolved in 10%sulfuric acid,10%sodium hydroxide or 10%sodium chloride aqueous solutions.ADPODS's emulsifiability and detergency at 650mg/L water hardness are very good.3 The adsorption of C₁₂-MADS on kalion is two stage adsorption with two molecular layers through the electrostatic and hydrophobic interaction between C₁₂-MADS molecular and kalion.The adsorption quantity increased by adding NaCl, but decreased by adding a little NaOH(0.005～0.01mol·L^-1),and then increased if excess NaOH added(0.10～0.40mol·L^-1).4 The oil/water interfacial tension of C₁₂-MADS system can be reduced to 4.00×10^-2mN/m,while the oil/water interfacial tension of C₁₂-DADS system can be reduced to 3.01×10^-3mN/m.ADPODS that can reduce the oil/water interracial tension are suitable surfactants for the tertiary recovery of crude oil.