Pre-treatment for the Resins

Industrial resin product often contains some excess solvent, oligomer and other impurities. These impurities must be removed, otherwise they will affect the exchange effect and effluent water quality. Thus new resin must be pretreated. Pretreatment and changing resin to needed ion form can improve resin’s stability and also have effect of resin activation.

1. Resin that left factory in a short time needs repeated water rinsing until effluent is clear, then follow the regeneration procedure.

2. Resin that left factory for a long time needs soaking in saturated salt solution. After soaking treatment, use water rinse repeatedly until effluent water is clear, and then follow the regeneration procedure.

3. For resins used in pharmaceutical and food industry, please make pretreatment according to specific requirement.

4. Cation resin pretreatment: use water wash resin until effluent is clear, soak the resin in 2- 4%NaOH solution for 3 - 6 hours and use water wash the resin to neutrality, after that soak the resin in 5% hydrochloric acid for 3 - 6 hours, use water wash the resin to pH=6, out water near neutral.

5. Anion resin pretreatment: use water wash resin until effluent is clear, soak the resin in 5% hydrochloric acid (HCl) for 3 - 6 hours and use water wash the resin to pH=6, after that soak the resin in 2- 4%NaOH solution for 3 - 6 hours, then use water wash the resin to pH=7-9, clear water to neutral.

Pollution, Poisoning and Activation of Ion Exchange Resin

In long-term operation, ion exchange resin is easy to get polluted by suspended matter, colloidal substance, organic substance, bacteria, algae, ion and manganese, resulting the ion exchange ability decrease or even lost. So, irregular activation must carry out according to situation. The activation method can be determined according to pollution situation and conditions, commonly, cation resin is easy to get polluted by Fe3+ in soften water, soak the polluted resin in hydrochloric acid and dilute gradually. Anion resin is easy to get polluted by organic substances, soak or spray wash the polluted resin by mixed solution of 10%NaCl + 2- 5%NaOH. If needed, soak the resin in 1% hydrogen peroxide solution for several minutes, or use acid-base alternating treatment method, bleaching treatment method, alcohol treatment method and other sterilization treatment methods.