Study On Synthesis And Properties Of Fatty Alcohol Polyoxyethylene Ether Sulfonate

Fatty alcohol polyoxyethylene ether sulfonates(AESO)is a kind of nonionic-anionic surfantant which adapt to the development of tertiary oil recovery technology.The molecular structure contains both nonionic surfactant hydrophilic group(methane oxygen group)and contains anionic surfactant hydrophilic group(sulfonic group).It can be resistant to salt resistant and high temperature.In addition,due to the sulfur directly connected in the carbon,the chemical stability is better than alcohol ether sulfate.Fatty alcohol polyoxyethylene ether 5(AEO-5)reacted with metallic sodium to form scodium polyehoxylated coconut fatty alcoholate,and the latter further reacted with Sodium 2-chloroethanesulfonate monohydrate in toluene as solvet to form the product fatty alcohol polyoxyethylene ether sulfonate,The influence of the reaction temnperture,reaction time,ceactant ratio on yield of product has been mainly discassed.The products were characterized by infrared spectra.The AESO were examined in thermal stability,salt resistance,emulsifying property,hard water resistance,foamability and surface properties.As a result,the optimum condition of synthesis was determined:reaction temperature was 64?,reaction time was 5 h,molar ratio of Sodium 2-chloroethanesulfonate monohydrate to sodium polyehoxylated coconut fatty alcoholate was 1.2:1,under this condition,the yield could reach the highest,which was 74.43%.The purity was 89.25%.The cmc of AESO was a little more than that of AES,but the ?cmc of AESO was lower than that of AES.That was to say,when reducing the surface tension,the efficiency of AESO was lower than that of AES,but the ability was better than that of AES.AESO rarely hydrolyzed within 24 h at 100?,its active matter content almost kept the same,but the AES hydrolyzed significantly.Moreover,the toleance of salinity(NaCl)of AESO was 152 g/L.Therefore its surface properties and thermal stability and salt resistance are much better than that of AES.The emulsifying performance tests have showed that the emulsification performance was best at the concentration of 1.25 g/L,with the increase of the concentration of NaCl,the emulsifiability of AESO was increased.Because of the EO groups,the solubility of AES and AESO was increased,their hard water resistance was better than that of lauryl sodium sulfate.When Ca2+and Mg2+ concentration reached 10000 mg·L-1,new phase was found in AESO solution,but not in AES.Though hard water resistance of AESO is lower than that of AES,it had reached a high level.Foamability test showed that AESO played best performance at the concentration of 1480mg/L,the foaming ability decreased with the increase of the concentration of Ca2+,Put the foam stability increased.Above all,AESO can be used in enhanced oil recovery with high temperature and high salinity.