The facile synthesis of zoledronate functionalized hydroxyapatite amorphous hybrid nanobiomaterial and its excellent removal performance on Pb2+ and Cu2

Abstract

In this paper, a simple chemical precipitation method was proposed to obtain zoledronate functionalized hydroxyapatite (zole-HAP) hybrid nano- biomaterials (zole-HAP-HNBM) which were firstly applied to adsorption. The characterizations of materials verified that the addition of zoledronate declined the crystallinity and transformed the morphology of HAP from short rod shape to microsphere, changed micro structure of the hybrid nanobiomaterial. Adsorption experiments carried out under different conditions showed that adsorption capacity of the nanobiomaterial, enhanced by the addition of zoledronate in preparation, which is equal to 1460.14 mg/g on Pb²⁺ and 226.33 mg/g on Cu²⁺ in optimum qualifications, was elevated more than the reported values in many literatures. At last, the sorption mechanisms of HAP and zole-HAP for Pb²⁺and Cu²⁺ were probed by experiments and Multifwn program calculation in details. It suggested that the dominant sorption mechanisms of HAP for Pb²⁺ were ion exchange and dissolution-precipitation rather than surface complexation, while besides the dissolution-precipitation mechanism, surface complexation may contribute more in the adsorption process of 10zole-HAP for Pb²⁺. Once considering HAP and 10zole-HAP, removal mechanisms of Cu²⁺ could involve surface complexation and ion exchange.

Keywords: Adsorption; Heavy metal ions; Hydroxyapatite; Multifwn program calculation; Removal mechanism.