The particle size distribution and the stability of toluene in water(O/W)emulsions were investigated by the variation of emulsifier concentration,addition pattern,emulsification method and emulsifier composition.Six nonionic surfactants and one anionic surfactant were employed to select the optimum composition of the binary system.The optimal composition is TX-4and sodium dodecyl benzene sulfonate(SDBS)at the ratio of 3∶7,concentration of5%,surfactants respectively dissolved in water and oil before emulsifi...