Fabrication of green one-part geopolymer from silica-rich vanadium tailing via thermal activation and modification

The aim of this investigation is to prepare geopolymeric precursor using vanadium tailing (VT) by thermal activation and modification. The homogeneous blend of VT and sodium hydroxide is calcinated at elevated temperature for activation and then was modified with metakaolin to assemble geopolymeric precursor. During the thermal activation, the VT is corroded by sodium hydroxide, and then forms sodium silicate on the particles surface. After water is added, the sodium silicate coating is dissolved to release silicon species and create alkaline solution environment, and then the metakaolin dissolved in the alkaline environment to provide aluminum species, followed by geopolymerization. Meanwhile, the VT particles are connected together by gel produced from geopolymerization, resulted in geopolymer with excellent mechanical performance. This investigation not only improves the feasibility of geopolymer technology in large-scale and in-situ applications, but also benefits the utilization of VT and other silica-rich solid wastes.