| 摘要 |
PURPOSE:To efficiently concentrate and separate a volatile organic liquid component with high separability, selectivity and permeation velocity by regulating the average pore diameter of a porous membrane to a value not less than specified times the Stokes' radius of objective substance for separation and holding the secondary side of the membrane at or above a specified pressure and flowing inert gas under specified conditions. CONSTITUTION:For example, a porous membrane consisting of a hydrophobic high polymer such as a hollow yarn membrane made of polyfluorovinylidene whose average pore diameter is regulated to a value not less than ten times the Stokes' radius of objective substance for separation and which is nonpermeable to a volatile organic liquid aq. soln. to be separated is used as a separation membrane. An ethanol aq. soln. or the like is fed to a membrane module 4 using this membrane. On the other hand, inert gas is passed through an inlet 12 of the secondary side of the membrane module and the permeating component discharged through an outlet 11 is collected with a cold trap 6. In this case, the pressure of the secondary side of the membrane is held at 150mmHg and above and the flow velocity of inert gas is regulated to 0.05-1.0m/s and the ratio of volumetric flow velocity of inert gas to volumetric velocity of permeating vapor is regulated to 0.02-1.0.
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