PURPOSE: To attain high separation coefficient and high filtration rate in the pervaporation separation of a liquid mixture of water and organic liquid having a specific concentration using a regenerated cellulose membrane, by pretreating the membrane with a liquid mixture of water and an organic liquid having a specific concentration and containing specific cation and anion.
CONSTITUTION: In the pervaporation separation of a liquid mixture of water and an organic liquid containing ≥85wt% organic liquid with a regenerated cellulose membrane, the membrane is pretreated, prior to the above separation process, by pervaporation method with a liquid mixture of water and organic liquid containing 40W80wt% organic liquid same to or different from the above organic liquid, and containing one or more cations selected from Mn2+, Fe2+, Co2+, Ni2+ Cu2+, Zn2+, Ce2+ and Mg2+ and one or more anions selected from SO42-, H2PO4-, CH3COO- and NO3- at concentrations not to cause the separation of the mixture into two phases, while keeping the concentration of the organic liquid in the mixture to the above level. The separation coefficient can be improved remarkably by the pretreatment and the above separation process can be carried out at high separation coefficient and high rate of permeation.
OGAWARA TAKASHI
SATO YOSHIO
YAMASHITA SHUZO
| JPS5433278A | 1979-03-10 |