Preparation and characterization of granular zeolite material from construction and demolition waste for lead removal

Abstract

To solve the separation problem of traditional artificial zeolite materials in a tiny powder size, zeolite particles (ZP) with a complex porous structure were synthesized from construction and demolition (C&D) waste. The synthesis method consists of two key processes: (1) converting C&D waste into porous ceramic particles through sintering; (2) transforming porous ceramic structure into zeolite structure through hydrothermal treatment. The obtained ZP contained porous structures on three dimension levels: millimetre, micrometre and nanometre respectively. XRD result showed that the ZP obtained, with a specific surface area of 45.6 m2 g–1, mainly consist of analcime. Afterwards, ZP were tested as granular adsorbents for heavy metal ion removal from aqueous system. Adsorption experiment results shown ZP was effective for the removal of lead(II), with a maximum adsorption capacity of 189.4 mg g–1. We show (1) an original method for converting C&D waste into environmentally functional materials, and (2) a novel, complex porous material for heavy metal removal from aqueous solutions.