Anion exchange resins are specialized materials used in water treatment and chemical processes to remove negatively charged ions, known as anions, from solutions. These resins contain positively charged sites that attract and hold anions, allowing for their separation from the liquid. Common applications include deionization of water and removal of contaminants like nitrates and sulfates. These resins are typically made from organic polymers and can be regenerated after use by flushing them with a concentrated solution of a suitable salt. This process restores their ability to capture anions, making them reusable and efficient for various industrial and environmental applications.