Used in water treatment processes to coagulate and remove suspended particles, organic matter, and phosphates from wastewater and drinking water. Effective in clarifying water by forming flocs that settle easily, improving filtration efficiency. Commonly applied in municipal sewage treatment plants and industrial effluent systems. Also utilized in the production of printed circuit boards for etching copper layers due to its oxidative properties. Serves as a reagent in analytical chemistry for detecting phenolic compounds, producing distinct color changes. Employed in laboratory settings for catalyzing organic reactions and in the synthesis of other iron-based chemicals.