离子液体水合物反应液表面张力的研究

Effect of ionic liquid on the liquid surface tension of hydrate formation

表面张力是衡量水合物动力学促进剂促进效果的主要参数,为了探究离子液体应用于水合物生成促进的可行性,实验合成了具有表面活性功能的离子液体[HMIPS]DBSA、[MIMPS]DBSA、[PIPS]DBSA和[PYPS]DBSA,并分别测定了在不同浓度及温度条件下的表面张力。结果表明:四种离子液体的最低表面张力相较于纯水均降低了一半以上,其中[MIMPS]DBSA的降幅最小;各离子液体的表面张力随着浓度的升高而降低并达到一定值,其中[MIMPS]DBSA的CMC浓度为700 ppm左右,其余三种离子液体的CMC浓度则均在900 ppm以上;此外,各离子液体的表面张力随着温度的升高而逐渐降低,但相较于浓度对其的影响,降幅要小得多。这说明浓度是影响水合物反应液表面张力的主要控制因素。可以发现所合成的离子液体与当前最好的促进剂SDS相比,有待于进一步优化。但离子液体的高度可设计性及生物可降解性给水合物促进剂的研发提供了广阔的发展空间,具有很好的发展前景。

Surface tension is a key parameter to measure the effectiveness of the kinetics of gas hydrates promoter.To study the feasibility of ionic liquids used to promote hydrate formation,[HMIPS]DBSA,[MIMPS]DBSA,[PIPS]DBSA and[PYPS]DBSA was synthesized in laboratory,and then surface tension of the ionic liquids was measured in different temperature and concentration.The results showed that,compared to pure water,the surface tension of these ionic liquids decreased by more than half and the falling range of surface tension in[MIMPS]DBSA is the smallest; the surface tension of the ionic liquid reduced to a certain value with the increase of concentration and[MIMPS]DBSA concentration of CMC is 700 ppm around.However,the CMC of other three kinds of ionic liquids is higher than 900 ppm.In addition,the surface tension of the ionic liquid reduced gradually with the rise of temperature,but the surface tension declined much smaller than the impact of the concentration. This shows that the concentration is the main controlling factor which affects liquid surface tension.In comparison to the best addictive（ SDS）,the synthesized ionic liquidsneedto be further optimized.However,the characters of the ionic liquid are strong design ability and biodegradability,which provides broad space for the development of hydrate promoters.