表面活性剂对气体水合物生成过程的定量影响

Quantitative Influence of Surfactant on the Formation Process for Gas Hydrate

为确定HCFC-141b水合物生成条件下阴离子表面活性剂十二烷基硫酸钠（SDS）和十二烷基苯磺酸钠（SDBS）的临界胶束浓度（CMC）,在0-20℃温度下,通过圆环法实验研究了不同浓度表面活性剂溶液体系的表面张力,考察了表面活性剂对溶液体系表面张力的影响机理并通过C3H8水合物的生成过程实验进行了验证,确定了SDS和SDBS的临界胶束浓度.结果表明,当SDS和SDBS的质量浓度分别低于500×10^-6和100×10^-6时,表面活性剂降低水表面张力的效果最明显,二者的CMC分别为1 950×10^-6和400×10^-6,表面活性剂能明显缩短水合反应的诱导时间,提高了其平均生成速率.

In order to confirm the critical micelle concentrations （CMC） of anionic surfactants sodium dodecyl sulfate （SDS） and sodium dodecyl benzene sulfonate （SDBS） under hydrate formation conditions, the surface tension of SDS and SDBS solution with different concentrations were measured by ring method in the temperature range of 0-20 ℃. The influence mechanism of surfactant on the surihce tension of solution system was revealed and verified through formation experiment of C3H8 hydrate, the CMC of SDS and SDBS solution under conditions of HCFC-141b hydrate formation were determined. The results showed that the effect of surfactant on surface tension decrease of water is most obvious when the weight concentration of SDS and SDBS solution was below 500×10^-6 and 100×10^-6, the CMC of SDS and SDBS solution are 1 950×10^-6 and 400×10^-6, respectively, near the conditions of HCFC-141b hydrate formation. Under the CMC, surfactant obviously promoted the formation process of C3H8 hydrate and shortened the induction time and increase the formation rate of gas hydrate.