INVESTIGATION ON THE ROLE OF ASPHALTENES AS STABILIZERS FOR TOLUENE-IN-WATER MINIEMULSIONS USING AN ELECTROSONIC ANALYSIS (ESA) METHOD

The study was aimed at investigating the role of asphaltenes as stabil izers for toluene-in-water miniemulsions. These miniemulsions were pre pared with sodium laurylsulphate and cetyl alcohol. To confirm the amp hoteric nature of the asphaltenes: 1) they were adsorbed on fluorite a nd their electrophoretic mobility was measured using a microelectropho resis cell and; 2) interfacial tension measurements were carried our u sing a tensiometer. The experiments reported here use the electrosonic analysis (ESA) method and were carried out on the ESA-8000 Analysis S ystem (Motec). It was experimentally observed that there is a direct r elationship between the ESA Potential and the asphaltenes content in t he miniemulsions. The pH influence on the ESA Potential of the alphalt enes-containing miniemulsions was investigated as well. A theoretical explanation for both phenomena is provided. To our knowledge, this is the first published attempt to determine the influence of asphaltenes on toluene-in-water emulsions stability using the ESA-8000 Analysis Sy stem.