Precautions of ion exchange resin

1. Ion exchange resin contains a certain amount of water and should not be stored in the open air. During storage and transportation, it should be kept moist to avoid air drying and dehydration, resulting in broken resin. If the resin is dehydrated during storage, it should be soaked in concentrated salt water (10%) and then diluted gradually. It should not be directly put into water to avoid rapid expansion and breakage of resin.

2. During storage and transportation in winter, the temperature should be kept at 5-40 ℃ to avoid supercooling or overheating, which will affect the quality. If there is no thermal insulation equipment in winter, the resin can be stored in salt water, and the concentration of salt water can be determined according to the temperature.

3、 The industrial products of ion exchange resin often contain a small amount of low polymer and non reactive monomer, as well as inorganic impurities such as iron, lead and copper. When the resin is in contact with water, acid, alkali or other solutions, the above substances will be transferred into the solution, affecting the quality of the effluent. Therefore, the new resin must be pretreated before use. Generally, the resin is fully expanded with water, and then the water is recycled The inorganic impurities (mainly iron compounds) can be removed by 4-5% dilute hydrochloric acid, and the organic impurities can be removed by 2-4% dilute sodium hydroxide solution. If it is used in pharmaceutical preparation, it must be soaked in ethanol.

4、 In use, the resin should be prevented from contacting with metal (such as iron, copper, etc.) oil stain, organic molecular microorganism, strong oxidant, etc., so as not to reduce the ion exchange capacity or even lose its function. Therefore, the resin should be activated irregularly according to the situation. The activation method can be determined according to the pollution situation and conditions. Generally, the cation resin is easy to be polluted by Fe during softening and can be soaked in hydrochloric acid The anion resin can be soaked or rinsed with 10% NaC1 + 2-5% NaOH mixed solution, soaked in 1% hydrogen peroxide solution for several minutes if necessary, and other methods can also be used, such as acid-base alternate treatment, bleaching treatment, alcohol treatment and various sterilization methods.

5. Pretreatment of new resin: the industrial products of ion exchange resin often contain a small amount of oligomer and monomer without reaction, as well as inorganic impurities such as iron, lead and copper. When the resin is in contact with water, acid, alkali or other solutions, the above substances will be transferred into the solution, affecting the quality of the effluent. Therefore, the new resin must be pretreated before use. Generally, the resin is expanded with water, and then the inorganic impurities (mainly iron compounds) can be removed with 4-5% dilute hydrochloric acid, and the organic impurities can be removed with 2-4% dilute sodium hydroxide solution until they are nearly neutral.