Abstract:

According to the solubilization behavior of methyl orange used as a solvation probe in the multiple system mixed by supercritical carbon dioxide,surfactants and cosolvents,this paper draws a conclusion that.under the ac-tion of n-butyl alcohol,the surfactants sodium bis-(2-ethylhexyl)sulfosuccinate(AOT)and isooctyl phenol poly-ethoxylate(TX-10)can form reverse micelles in supercritical carbon dioxide.The formation of the micelles is spontaneous in therm odynamics．Specifically,for nonionic surfactant TX-1 0,the form ation of the micelles depends on the increase in entropy,while for anionic surfactant AOT,the form ation mainly depends on the increase in enthalpv at a high temperature and on the increase in entropy at a low temperature.

Key words: supercritical carbon dioxide, reverse micelle, surfactant, probe, thermodynamics