Used as a catalyst in organic synthesis, particularly in chlorination reactions and Friedel-Crafts alkylation. Employed in the production of flame retardants, where it enhances the fire resistance of materials when combined with halogenated compounds. Utilized in analytical chemistry for the detection of vitamin A and carotenoids through the Carr-Price test, producing a characteristic blue color. Also applied in the manufacturing of antimony-based chemicals and specialty glasses with infrared transmission properties. Handling requires caution due to its corrosive and moisture-sensitive nature.