水相中乙醇对胶体泡沫性质的影响

Influence of Alcohol on the Properties of Colloidal Liquid Aphrons

用不同比例的水-乙醇混合物作水相制备了胶体泡沫(CLA),实验观察并测定了CLA的形态、粒径分布、半衰期、Zeta电位、水相溶液的粘度和水相/油相之间的界面张力等性质.结果表明,水相中加入乙醇会影响CLA的稳定性和粒径大小,但对CLA的Zeta电位影响不大.乙醇对CLA稳定性的影响主要是由于乙醇分子嵌入到界面膜中导致膜的强度变化以及水相粘度发生变化导致CLA粒子间隙的排液过程发生变化.

This work examined the shape,half life,Zeta potential and other properties of colloidal liquid aphrons (CLA),whose aqueous phase is composed of de ionized water and alcohol.The volume ratio of water to alcohol varies while the concentration of water soluble surfactant does not change.It is found that the existence of alcohol in the aqueous phase will affect the surface tension between the oil and water phase,hence the particle size and distribution of CLA will change.The influence of alcohal on the Zeta potential of CLA is very weak.The main cause of the change of stability is that alcohol molecule is embedded into the SDBS layer and a mixed soapy film is formed,which changes the intensity of the soapy film .The viscosity of the aqueous phase change also,which affects the process of drainage.When the concentration of alcohol reaches 30%,the most stable CLA appears,while the worst stable one appears at 50%. In the application of pre dispersed solvent extraction,we need a stable and small sized CLA with a large matter transferring area,and the cost should be low.This will be benefit for the industrialization of the method.The results of this work prove that by adding alcohol into the aqueous phase ,we can get the CLA with great satisfactory for industrial use.