PROBLEM TO BE SOLVED: To provide a preservation liquid for separation membranes having high safety and excellent handling easiness, free from the lowering of performance by the deterioration of the separation membrane and capable of suppressing the proliferation of bacteria and molds for a long period, a separation membrane module having excellent long-term preservability, resistant to the discoloration and foaming caused by the preservation liquid and having little restriction on the packaging material and preservation environment, and a method for the preservation of separation membranes.SOLUTION: The preservation liquid for separation membranes is composed of an aqueous solution containing benzoic acid and/or a benzoic acid salt in an amount of preferably 0.05-0.5 mass%. The preservation liquid for separation membranes preferably has a pH of &le4.5 at 25°C, a separation membrane module is filled with the preservation liquid for separation membranes, and a method for preservation of a separation membrane includes immersion of the separation membrane in the preservation liquid for separation membranes.COPYRIGHT: (C)2007,JPO&INPIT【課題】 安全性が高く取扱い性に優れ、さらに分離膜の劣化による性能低下がなく、細菌や黴の繁殖を長期間抑制することができる分離膜用保存液の提供。長期間の保存性に優れ、保存液による着色や泡立ちが発生しにくく、梱包材や保管環境の制約が少ない分離膜モジュールや分離膜の保存方法の提供。【解決手段】 安息香酸及び/又は安息香酸塩を好ましくは0.05~0.5質量%の範囲で含む水溶液からなる分離膜用保存液。好ましくは25℃におけるpHが4.5以下である上述の分離膜用保存液。上述の分離膜用保存液が充填されている分離膜モジュール。分離膜を上述の分離膜用保存液に浸漬する、分離膜の保存方法。【選択図】 なし
