Zirconium-Modified Sweet Orange (Junar) Peel for Efficient Removal of Phosphate from Water

Abstract

Phosphate pollution poses a major threat to aquatic ecosystems, causing eutrophication and degrades aquatic system. Despite numerous reported adsorbents, the lack of viable low-cost, and efficient bioadsorbents remains a critical research gap. This study investigates zirconium (IV)-modified saponified sweet orange (Junar) peel powder (Zr(IV)-SJP) as an eco-friendly biosorbent for removing phosphate from water. Batch experiments were conducted with zirconium (IV)-modified saponified sweet orange (Junar) peel powder (Zr(IV)-SJP). Maximum phosphate removal was achieved at pH 4, with equilibrium reached within 150 minutes. Adsorption followed pseudo-second-order (PSO) kinetics and the Langmuir isotherm, with adsorption capacity of 114.03 mg/g. Characterization using FTIR and XRD confirmed the successful modification and strong affinity of Zr(IV)-SJP toward phosphate ions. These results highlight Zr(IV)-SJP as a cost-effective, eco-friendly bioadsorbent capable of efficiently mitigating phosphate contamination in water.