Used in water purification systems to remove impurities and control pH by exchanging hydroxide ions for anions like chloride, sulfate, and bicarbonate. Commonly applied in deionization processes to produce high-purity water for laboratories, pharmaceuticals, and boiler feedwater. Also utilized in conjunction with cation exchange resins in mixed-bed systems for complete demineralization. Plays a role in wastewater treatment by removing harmful anions and in chemical synthesis for base generation and catalyst recovery.