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The new liquid-liquid separation method with asymmetric plate-type microchannel was successfully used to de-emulsify the kerosene in water (K/W) emulsions.Three types (PTFE-PTFE,PTFE-SS and SS-SS) of microchannels with clearances from 48~195 μm were experimented to de-emulsify the K/W emulsion with different Sauter diameters of 5~10 μm made by high-shear homogenization method.The mix nonionic surfactant (Tween80 and Span80) had been used as emulsifier to prepare kerosene in water (K/W) and water in kerosene (W/K) emulsions.For K/W emulsion with Sauter diameter of 10 μm,the best result of 40% efficiency was achieve by single passing through the PTFE-PTFE-100 microchannel,and up to 80% efficiencies were achieved by repeatedly passing through PTFE-PTFE-100 and PTFE-SS-100 microchannels.However,for W/K emulsion,poor de-emulsification efficiency was observed.The de-emulsification process of emulsion stabilized with Tween80+Span80 was different from the de-emulsification of emulsions stabilized with the anionic surfactant SDS (sodium dodecyl sulfate) which was reported in 20101,and there were apparent big droplets in the exported emulsion and it took 3~5 minutes for the K/W emulsion to initial the liquid-liquid separation.The de-emulsification efficiency would continue increasing until stabilizing after the emulsions were statically creamed for ~30 minutes.The experiments results showed that the de-emulsification efficiency was influenced by the flow rate,Sauter diameter,microchannel size,and wall materials.The experiments results can be explained well based on ‘confined-coalesce’ mechanism,and we believe the different de-emulsification phenomenon result from different stability mechanism (ionic vs nonionic) of emulsions.The capillary number (Ca=ηmγR/σ),the confinement ratio (d/H),the slip condition and high specific surface (S/A) were key factors affect the de-emulsification efficiency of microchannel.Specially,the extra de-emulsification efficiency of PTFE-SS microchannel was observed,and it was certified again that the asymmetrical combination of PTFE-SS microchannel induced an asymmetrical velocity profile between two plates,which helped the droplets captured by the PTFE wall.