| 摘要 |
PURPOSE:To obtain the title reverse osmosis membrane capable of separating a soln. of salts in remarkably high degree by allowing a metal to exist locally in the vicinity of the surface of a cellulose derivative membrane in high concn. CONSTITUTION:A polymer consisting of a cellulose derivative and org. additives such as maleic acid and butane tetracarboxylate are dissolved in a solvent consisting essentially of dioxane, and a film is formed from the soln. When the obtained reverse osmosis membrane is then heat-treated, metals such as Fe, Ti, Pb and Cr having >=4sp.gr. are added to a heat treating bath in the form of ions, chelates and elements. Concretely, inorg. salts such as ferric sulfate, ferric chloride and ferric nitrate are preferably used. The heat treating temp. is preferably controlled in the temp. range 30-95 deg.C. Consequently, a reverse osmosis membrane on the surface layer part of which metals are distributed in high concn. can be obtained. |
