摘要 |
PURPOSE:To remove salts contained in a liq. efficiently, by treating the liq. contg. the salts with a mixed bed consisting of three dimensional polyethylene imine and a weakly acidic cation exchange resin. CONSTITUTION:A three dimensional polyethylene imine contg. primary-quarternary amino groups formed by treating polyethylene imine with a multifunctional cross linking compound, e.g., ethylene dibromide, parachloromethyl benzene to form a three dimensional structure and a weakly acidic cation exchange resin contg. carboxylic acid, e.g., (meta)acrylic acid, are mixed in an equivalent ratio of 0.1-10 to form a mixed bed. The mixed bed is then used to desalt the liq. contg. dissolved salts in a total concn. not larger than 3,000ppm by treating at a temp. 5-40 deg.C. The mixed bed having adsorbed salts is regenerated by use of hot water at a temp. 70-110 deg.C. |