Caustic Soda Flakes, or sodium hydroxide, are highly corrosive and versatile chemicals. They are used in the manufacturing of soaps, detergents, and various chemical processes. Caustic soda is also used in the petroleum industry for refining, in water treatment to remove hardness, and in paper production for pulping. In the food industry, it is used for processing certain foodstuffs, such as olives and cocoa.