Synthesis of Hydroxyapatite–Zeolite Composite Material from Disposed Steel Slag and Investigation of Its Structural and Physicochemical Characteristics

Abstract Steel slag is a commercial waste material mainly containing SiO2, Al2O3, and CaO which are the chemical components of zeolite and hydroxyapatite (HAP), respectively. From the steel slag, a hydroxyapatite–zeolite composite material (HAP–ZE) was successfully synthesized in a one batch system by adding H3PO4 and NaOH. The structural characteristics of HAP–ZE were investigated by XRD, SEM, and N2 adsorption. From the adsorption of VOCs, HAP–ZE was found to have adsorption properties comparable to those of pure zeolite and HAP.