Study On Synthesis And Performance Of Aliphatic Alcohol (Alkylphenol) Polyoxyethylene Ether Sulfonates

Aliphatic alcohol (alkylphenol) polyoxyethylene ether sulfonates are a class ofimportant anionic–nonionic surfactants with excellent properties such as good salttolerance, good heat resistance and high surface activity, so it possess a greatapplication potential in oil production of high temperature and high salinity Oilfield.However, its synthesis is so difficult that its practical application has being limited.Therefore, so it is important to study the synthesis and performance ofpolyoxyethylene ether sulfonates.In this paper, aliphatic alcohol (alkylphenol) polyoxyethylene ether sulfonateswere synthesized by etherification with aliphatic alcohol (alkylphenol) ethoxylates andsodium isethionate as raw materials. The results indicated that the above reaction couldbe efficiently promoted and the yield of the product could be markedly improved bythe combination of phase-transfer catalysis and superdispersion. The foam could beefficiently depressed and the flash could be prevented by using superdispersant. Theoptimum conditions were found as follows: n(ethers):n(sodiumisethionate):n(KOH):n(PTC)=1:1.4:0.36:0.06, w(superdispersant):w(ethers)=20:33，thereaction temperature being160~165℃，the reaction time being5h. Under the aboveconditions,12kinds of polyoxyethylene ether sulfonates were synthesized with theyield of more than65%except4S with50.59%and6S with64.27%, and the yield of5S was up to86.24%.Performance results showed that the surface activity of polyoxyethylene ethersulfonates was reduced, but its solubility in the brine and the cloud point wereimproved with the increase of the polymerization degree of the polyoxyethylene chain;Salt tolerance and solubility are also effected by type of hydrophobic chains of the sulfonates, the solubility of aliphatic alcohol polyoxyethylene ether sulfonates issuperior to alkylphenol polyoxyethylene ether sulfonates in brine; the cloud point ofpurified product in brine is obviously improved, and the cloud point of crude productis increased with the degree of polymerization of the polyoxyethylene chain, but thecloud point of all crude product is less than100℃in10×104mg/L standard saline,while the cloud point of all purified product are greater than102℃and105℃respectively in4×104mg/L and10×104mg/L standard saline, but surface (interfacial)tension of purified products is significantly greater than crude products. Polyoxyethylene ether sulfonates showed almost no hydrolysis when heated24h at130℃, and no detectable change in surface(interfacial) tension, which indicated thatthe sulfonates possess satisfying high temperature hydrolysis resistance; The idealproducts were11S and4S, when their concentration was0.5g/L, the surface tension in10×104mg/L normal saline were26.37mN/m and27.11mN/m respectively,interfacial tension were0.65mN/m and0.53mN/m respectively, the cloud point were80℃and87℃respectively.