Question

The exhausted cation exchange resin can be regenerated by the moderately concentrated sodium hydroxide solution. State True or False.

• A. True
• B. False
• C. Cannot be detrmined
• D. None of the above

Answer 1

The correct option is A True

The exhausted cation exchange resin can be regenerated by moderately concentrated H2SO4 solution.
Cation exchange resin is used to remove cations such as $N{a}^{+},C{a}^{2+}M{g}^{2+}$ from hard water. Cation exchange resins contains $-S{O}_{3}H$ or $-COOH$ groups. $H^{+}$ ions from these groups are replaced with $N{a}^{+},C{a}^{2+}M{g}^{2+}$ ions from hard water and the cation exchange resin is exhausted. To regenerate exhausted cation exchange resin, it is passed through concentrated $H_{2}S{O}_4$ solution. $H^{+}$ ions (from concentrted $H_{2}S{O}_4$ solution) replaces $N{a}^{+},C{a}^{2+}M{g}^{2+}$ ions from exhausted cation exchange resin to regenerate cation exchange resin.