| 摘要 |
PURPOSE:To recover permeability of a semipermeable membrane and to keep the permeability for a long time through washing for a short time under such mild condition that may not damage the membrane, the washing by semipermeable memberane with an aq. mixed soln. of neutral detergent and citric acid whose pH is adjusted in a specific range by addn. of alkali hydroxide. CONSTITUTION:Cellulose acetate semipermeable membrane contaminated through treatment of oil-contg. emulsified waste water, activated-sludge-treated water, or sugar manufacture waste soln. is waste soln. is washed by the following method: The contaminated semipermeable membrane is washed with an aq. mixed soln. of a neutral detergent and citric acid after its pH is adjusted in the range 2-6, pref. 3-6 by addn. of one or more of NH4OH, NaOH, KOH. |
