不同表面活性剂对石油醚微乳液性能的影响研究

Effect of Different Surfactants on the Properties of Petroleum Ether Microemulsion

研究了不同表面活性剂对石油醚微乳液性能的影响。选取壬基酚聚氧乙烯基醚(TX-4)、仲烷基磺酸钠(SAS60)和SAS60/TX-4复合表面活性剂,并将无水乙醇、正戊醇、正辛醇作为助表面活性剂进行试验,分别复合表面活性剂、助表面活性剂、水与石油醚构成微乳液。经试验分析可知:选用正戊醇作为助表面活性剂能够降低微乳液的表面张力,使微乳液的水溶性更强;三种表面活性剂中,SAS60/TX-4的拟三元相图微乳区面积最大,该表面活性剂能够迅速溶于水相,加快微乳液的形成并增强微乳液界面膜的流动性;利用SAS60/TX-4作为表面活性剂时,在试验温度30℃下,微乳液的稳定性最高,且不同盐度不会对微乳液造成太大影响,加入1.0%盐时,微乳液的稳定性最低,而加入0.4%盐时,微乳液的稳定性最高;同时,SAS60/TX-4具有较高的析出时间,达到110s以上,因此其乳化性能较好,进行高速离心加速试验时,SAS60/TX-4制备出的微乳液未出现水油分离现象,因此,SAS60/TX-4具有较高的稳定性。

The effects of different surfactants on the performance of petroleum ether microemulsion are studied.The nonylphenol polyoxyethylene ether(TX-4),secondary alkyl sulfonate(SAS60)and SAS60/TX-4 composite surfactants are selected.And the anhydrous ethanol,n-amyl alcohol and n-octanol are used as cosurfactants.The microemulsions is composed of surfactants,cosurfactant,water and petroleum ether.The experimental analysis shows that the use of n-amyl alcohol as cosurfactant can reduce the surface tension of microemulsion,and make the water solubility of microemulsion stronger.Among the three kinds of surfactant,the pseudo-ternary phase diagram of SAS60/TX-4 has the largest area of microemulsion,which can rapidly dissolve in aqueous phase,accelerate the formation of microemulsion and enhance the fluidity of microemulsion interfacial film.When the SAS60/TX-4 is used as surfactant,the stability of microemulsion is the highest when the test temperature is 30℃,and the salinity has no great effect on the microemulsion.When adding 1%salt,the stability of the microemulsion is the lowest,while the stability of the microemulsion is the highest when adding 0.4%salt.At the same time,the SAS60/TX-4 has a higher precipitation time which reaches 110s,so its emulsification property is better.In the process of high-speed centrifuge accelerated test,the microemulsion produced by SAS60/TX-4 does not appear the phenomenon of water oil separation.Therefore,the SAS60/TX-4 has a high stability.