Preparation of novel porous hydroxyapatite sheets with high Pb2+ adsorption properties by self-assembly non-aqueous precipitation method

Abstract

Herein, novel porous hydroxyapatite sheets with high pore homogeneity are prepared via a self-assembly nonaqueous precipitation method. The optimized calcium source, phosphorus source and solvent are calcium acetate, disodium hydrogen phosphate and glycerin, respectively. Hexagonal plate-like hydroxyapatite polycrystals form in the replacement-rearrangement groups of raw materials and grow along the (002) crystal plane of the hydroxyapatite phase. Large hydroxyapatite sheets have homogeneous pore sizes of approximately 110 nm and thicknesses of approximately 20 nm. The hydroxyapatite sheets prepared via the nonaqueous precipitation method are highly active carbonate apatite. In a nonaqueous environment, assembly units of hexagonal plate-like hydroxyapatite polycrystals are triggered by the replacement and rearrangement of groups in the raw materials, and they self-assemble to form large hydroxyapatite sheets in the form of edge sharing. The degree of curvature in the process of plate-like hydroxyapatite self-assembly triggers the formation of porous hydroxyapatite sheets. This material has excellent adsorption performance for Pb2+ ions. The material developed in this work has wide application prospects in the fields of adsorption treatment of wastewater containing toxic ions (such as Pb2+), and it is expected to become a novel type of lead ion adsorbent.