不同表面活性剂对甲烷水合物生成的影响

Effect of different surfactants on methane hydrate formation

为探究表面活性剂对于水合物生成的促进机理,文章选取了阴离子表面活性剂十二烷基硫酸钠(SDS),阳离子表面活性剂十二烷基三甲基溴化铵(DTAB)和非离子表面活性剂脂肪醇聚氧乙烯醚(AEO)进行甲烷水合物的生成实验。测试了表面活性剂的特性(如临界胶束浓度)、表面活性剂溶液在反应釜内表面的润湿性对水合物生成过程的影响,并对DTAB进行搅拌增强实验。实验结果表明:以DTAB和AEO为促进剂时,促进机理为胶束作用,水合物在反应釜底部生成;以SDS为促进剂时,水合物在气/液/固三相交界处开始生成,由于形成多孔结构的水合物,可以利用毛细作用不断的促使反应液与气体保持接触,从而使其对水合物生长的促进效果更佳。

To study the effects of different surfactants on methane hydrate formation, anionic sodium dodecyl sulfate （SDS）, cationic dodecyltrimethylammonium-bromide （DTAB） and nonionic dodecyl alcohol ethoxylates （AEO） were used in methane hydrate formaiton. The effects of the properties of surfactants （such as critical micelle concentration） and wettability of surfactant solutions on inner face of reactor sidewall to methane hydrate formation was studied. The results showed that the promotion mechanism of DTAB and AEO to methane hydrate formation was micelle effects. For SDS, the hydrate formed initially at the gas/liquid/solid interline as porous structures, which could keep the continuous gas/liquid contact under the capillary effect.