<p>Treatment of fluorine-containing wastewater remains challenging. This study proposes a closed-loop method involving acidification, adsorption, alkaline elution, and regeneration for fluoride removal from wastewater using anhydrous zirconium sulfate (Zr(SO₄)₂) as a defluorination agent. Firstly, Zr(SO₄)₂ was synthesized via acidification of ZrO₂ with sulfuric acid (H₂SO₄). Secondly, under the optimal conditions of pH 4, temperature of 60°C, adsorption time of 60 min, and Zr(SO₄)₂ dosage of 1.2 g/L, the fluoride removal rate of 96.52% was achieved. The fluoride removal residue was eluted with sodium hydroxide solution, yielding a maximum fluorine elution rate of 99.78% at 1 mol/L NaOH. Subsequent re-acidification of the eluted residue with H₂SO₄ regenerated the defluorination agent. Over 10 cycles, the fluoride removal rate remained consistently above 90%. Adsorption kinetics analysis indicated that the process followed the pseudo-second-order kinetic model and the Langmuir model, with a maximum adsorption capacity of 139.86 mg/g. Material characterization revealed that fluoride adsorption on Zr(SO₄)₂ occurred mainly through chemical adsorption, forming a ZrF₄ conjugate. These results demonstrate that Zr(SO₄)₂ is a promising defluorination agent for industrial wastewater treatment, enabling effective fluoride removal with low consumption.</p>