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Instructions for use of ion exchange resin

Jun 08, 2020

1. Resin storage method

Ion exchange resin cannot be stored in the open air. The temperature of the storage place is 0-40 ℃. When the storage place temperature is slightly lower than 0 ℃, clear saturated saline should be added to the packaging bag to soak the resin. In addition, when the storage temperature is too high, it not only makes the resin easy to dehydrate, but also accelerates the degradation of the anion resin. Once the resin loses water, water cannot be added directly during use. It can be soaked in clear saturated saline, and then gradually diluted with water to wash away the salt. It should be kept moist during storage.

Second, resin pretreatment

The new resin to be used for packing is first washed repeatedly with hot water (clean tap water). The cation exchange resin can use 70-80℃ hot water, and the anion exchange resin has poor heat resistance, 50-60 ℃ hot water. At the beginning of the immersion, change the water every 15 minutes. Stir occasionally during the immersion. After changing the water 4-5 times, you can change the water every 30 minutes. The total water change is 7-8 times. The washing water does not have brown color, and there is little foam.

After washing with water and then acid-base treatment, the cation exchange resin can be treated as follows:

1. Slowly flow through the resin with 1N hydrochloric acid, the amount is about 2-3 times the volume of the strong acid cation resin, and 1.5 times the bed volume per hour.

2. Rinse with water, the PH of the effluent is about 5, use 3 times the volume of resin 5% NaCl solution to flow through the resin, the flow rate is the same as 1.

3. Use 1N NaOH to flow through the resin with the same dosage and flow rate as 1.

4. Rinse with water until the PH of the effluent is around 9.

5. Use 1N hydrochloric acid or sulfuric acid to convert the resin to H type, the dosage is 3-5 times the volume of the resin, and the flow rate is the same as 1.

6. After the acid flow is completed, rinse with deionized water until the PH value of the effluent is above 6, and then it can be put into use.

For the order of acid and alkali treatment after anion exchange resin is washed with water, the order of alkali→acid→alkali, acid and alkali dosage and flow rate can be used. Strong alkali resin corresponds to strong acid resin, weak alkali resin corresponds to weak acid resin.

3. Resuscitation treatment of resin

In the process of using ion exchange resin, after a period of operation, the quality of the effluent will gradually decline and the exchange capacity will gradually decrease. This is generally due to contamination of the resin during operation. In the extraction of wastewater and biochemical substances, due to the more complex ingredients, the resin is more susceptible to pollution, so appropriate measures should be taken for resurrection treatment, and different resurrection treatment processes are used for different situations.