Widely used in water and wastewater treatment as a coagulant to remove suspended solids, phosphates, and heavy metals. It helps clarify water by forming flocs that settle easily, making it effective in both drinking water purification and sewage treatment. Commonly employed in the electronics industry for etching copper in printed circuit board (PCB) manufacturing due to its ability to oxidize and dissolve metal layers. Used in chemical synthesis as a catalyst or reagent, especially in organic reactions such as Friedel-Crafts alkylation and chlorination processes. Applied in the leather tanning industry to treat hides and improve durability. Also utilized in the production of other iron-based chemicals and pigments. In some medical applications, it serves as a hemostatic agent to control bleeding in minor cuts and dental procedures.