Preparation and characterization of tungsten tailing-based geopolymers

Using tailings to prepare constructive materials is of great significance for sustainable development of mineral processing industry. In this study, the possibility of preparing tungsten tailing-based geopolymers was explored in detail. XRD, FTIR, PLM, SEM and XPS analyses were carried out to characterize the phase composition, chemical bonding, microstructure, chemical state, and interface properties of tungsten tailing-based geo-polymers. Results showed tungsten tailings presented little activity using NaOH as activator, while geopolymers with 60% non-pretreatment tungsten tailing and 40% metakaolin presented a 3-day compressive strength of 8.4 MPa and 28-day compressive strength of 9.1 MPa. The geopolymerization products of tungsten tailing-based geopolymers were N-A-S-H gels and aluminosilicate zeolite crystals, while tungsten tailings were wrapped by metakaolin-derived geopolymerization phases as aggregates with interfaces containing Si-O-Si bonding between quartz in tungsten tailings and zeolite and/or gel phase in metakaolin-derived geopolymer in the geo-polymerization process. Besides, the leaching test results indicated that the immobilization efficiency of T6M4 geopolymers for Mn and Pb derived from tungsten tailings reached up to 97.28% and 99.95%, respectively. This research results provide a new idea for utilization of tungsten tailings on a large scale.

Automated summary

Using tailings to prepare constructive materials is important for sustainable development of the mineral processing industry. This study explored the possibility of preparing tungsten tailing-based geopolymers. Various analyses were conducted to characterize the composition, bonding, microstructure, and properties of the geopolymers. Results showed that geopolymers with a mixture of tungsten tailings and metakaolin had good compressive strength and could immobilize heavy metals efficiently. This research provides a new idea for the utilization of tungsten tailings on a large scale.