Development of highly efficient bundle-like hydroxyapatite towards abatement of aqueous U(VI) ions: Mechanism and economic assessment

Abstract

The exploration of emergency materials with ultra-fast adsorption rate and great adsorption capability of released U(VI) ions is essentially urgent. The present work successfully fabricated bundle-like hydroxyapatite (B-HAP) microstructures which composed of numerous nanorods by employing a facile and green method. The B-HAP was applied to treat the U(VI) containing wastewater. The abatement of U(VI) by B-HAP was very rapid and the saturated adsorption capacity was superior; over 96.7 % of U(VI) was abated within 5 min, and the maximum adsorption capacity was as high as to 1305 mg/g, signifying the feasibility and effectiveness of this B-HAP in the treatment of uranium-contaminated wastewater due to nuclear accidents. It is worthy to note that other ions in solution exhibited relatively low interference on its performance, indicating that B-HAP has great application potential to capture U(VI) from radioactive-contaminated wastewater as well. The U(VI) removal mechanism by B-HAP was confirmed with results from XRD, FT-IR and XPS. Chernikovite [H2(UO2)2(PO4)2·8H2O] was newly formed after U(VI) abatement by B-HAP. Economic assessment suggested B-HAP and its application on U(VI) abatement were cost-effective. With characteristics of high adsorption rate, large capacity, and strong antijamming ability, B-HAP has great application potential as an emergency treatment material for nuclear accidents.