How to pretreat ion exchange resin?

(1) Pretreatment steps of cation exchange resin

First, wash the resin with clean water (preferably Zhi backwashing) until the water is clear without Dao turbidity and impurities. Then soak 4~5% HCl and NaOH alternately in the exchange column for 2~4 hours, and rinse with a large amount of clean water between the acid and alkali (preferably with mixed bed high-purity deionized water) until the effluent is close to neutral. Repeat this for 2~3 times, and the amount of acid and alkali used each time is twice the volume of the resin. Compared with the last treatment, it is better to use 4~5% HCl solution to double the dosage. Drain the acid solution and rinse it with clean water until it is neutral.

(2) Pretreatment steps of anion exchange resin

First, wash the resin with clean water (preferably backwashing) until the water is clear without turbidity and impurities. Then soak 4-5% NaOH and HCl alternately in the exchange column for 2-4 hours, and rinse with a large amount of clean water between alkali and acid (preferably with mixed bed high-purity deionized water) until the effluent is close to neutral. Repeat this for 2-3 times, and the amount of acid and alkali used each time is twice the volume of the resin. Compared with the latter treatment, it is better to use 4~5% NaOH solution to double the dosage. Drain the lye and rinse it with clean water until it is neutral.