Dilute Acid or Alkaline Solutions Are Required for Ion Exchange Resin Regeneration

The ion exchange resin should not be stored in the open air, and the temperature of the storage place should be 0–40 °C. When the temperature of the storage place is slightly lower than 0 °C, clarified saturated salt water should be added to the package bag to soak the resin. In addition, when the temperature of the storage place is too high, it will not only make the resin easy to dehydrate, but also accelerate the degradation of the anion resin. Once the resin loses water, you cannot add water directly when using it. You may soak it in clarified saturated salt water and then add water gradually to dilute it, wash away the salt, and keep it moist during storage.

Among the industrial products of ion exchange resin, they often contain a small amount of organic oligomers and some inorganic impurities. The new resin will gradually dissolve and release in the early stage of use, affecting the permeate quality or product quality. Therefore, pretreatment must be carried out before use. The specific methods are as follows.

1. When the resin is loaded into the exchanger, backwash the resin layer with clean water at 50%–70% unfolding rate until the effluent is clear, odorless and free of finely ground resin;
2. Pass through the resin layer with 4%–5% HCl solution of about 2 times the volume of resin at a flow rate of 2 m/h. After all the solution passing through, soak for 4–8 hours, drain the acid solution and rinse with clean water until the effluent is neutral, with a flow rate of 10–20 m/h.
3. Pass through the resin layer with 2%–5% NaOH solution of about 2 times the volume of resin at a flow rate of 2 m/h. After all the solution passing through, soak for 4–8 hours, drain the alkali solution and rinse with clean water until the effluent is neutral, with a flow rate of 10–20 m/h.
4. It would be more effective if the acid and alkali solution can be repeated 2–3 times.
5. After pretreatment, the amount of regenerant should be increased appropriately when the resin is put into operation for the first time to ensure that the resin is fully regenerated.

• Resin regeneration requires dilute acidic solutions or alkaline solutions. When diluting acid and alkali solutions, you need to wear plastic or rubber apron and gloves, protective glasses and mask . When the acid or alkali solution splashes into the skin or eyes, flush with plenty of water. If there is redness, swelling, pain, etc., go to the hospital for treatment timely.
• Do not touch the resin in the package directly with your hands to avoid skin allergy. If you touch it directly with your hands, you may rinse it off directly with water.
• If resin is accidentally ingested, go to the hospital for treatment immediately.
• Do not dispose of the waste resin arbitrarily. Put it in the finished packaging container and hand it over to professional units for incineration to avoid polluting the environment.
• There will be some by-products generated in the resin manufacturing process. Users need to know the types and amounts of by-products generated and to be removed during the use of resin. Take appropriate methods to ensure the purity of resin during using.
• When using nitric acid or other strong oxidizing agents, it may cause explosive reactions by mixing with resin. So, when designing the equipment, care needs to be taken to prevent sudden pressure increases.