Separation of butyl acetate from model emulsions by solvent sublation

Separation of butyl acetate from the O/W type model emulsion by solvent sublation with Span-80 as the emulsion surfactant was studied. The particle size and zeta potential were analyzed by particle size analyzer and emulsion stability was characterized by concentration measurement. The effects of gas rate, operating time, surfactant concentration, solute concentration, pH and cosolutes (NaCl and ethanol) on the removal efficiency and the particle size and zeta potential were investigated. It was found that only droplets with the diameter larger than 500 nm can be removed from the model emulsions by solvent sublation. Under that condition, the separation efficiency of solvent sublation was somewhat increased in comparison with that of solvent extraction when the solution was in emulsion type. Comparison of removal efficiency was made between the aqueous saturated solution and model emulsion. Results showed that the emulsion property of the solution improved the separation.