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In this paper, an investigation was conducted on the effects arising from albite, K-feldspar, quartz (three particle sizes) and muscovite (two particle sizes) of spodumene flotation tailings on ceramics, as well as the corresponding crystal changes. As indicated by the results, albite and K-feldspar positively impacted the strength of ceramic materials. The flexural strength of ceramics was increased with the decrease in the particle size of quartz. The flexural strength and linear shrinkage of ceramic materials was increased with decreased particle size of muscovite. The melting of albite and the formation of eutectic phase from albite and quart filled the pores between mineral particles, which were found as the major sintering mechanism of ceramics. Furthermore, during the sintering process, the crystal phase transformation of α-quartz to β-quartz and the de-hydroxylation of muscovite and kaolinite was occurred. Lastly, tailings have the potential to be used as raw materials for ceramic materials. Quartz could be used as ridge materials and green materials for permeable ceramics, albite could be used as flux for low temperature sintered ceramics, and muscovite could be used to prepare mullite refractories. [Display omitted] [ABSTRACT FROM AUTHOR]

This work explored the use of spodumene flotation tailings (SFT) as an aggregate used in cement mortar to mitigate their environmental impact. The principal phase compositions of SFT were quartz (Qtz), feldspar (Fsp) and muscovite (Ms). So, the effects of variations in the particle size of Qtz, and mineral additives, Ms and Fsp, on the compressive strength and hydration products were examined. Ms additives imparted the lowest compressive strength. Finer Qtz aggregates (4000–106 µm) reduced the nano-pore volume, and Ms increased the nano-pore width of cement mortar. In addition, fewer hydration products, and poor crystallinity of both ettringite (Aft) and portlandite resulted in a decrease in the compressive strength of the cement mortar, eventually. Therefore, increasing the particle size or optimisation of the mineral composition of SFT could provide a facile route to improving the mechanical properties of cement mortars. [Display omitted] • SFT results fewer hydration products, and poor crystallisation. • A reduction in the Qtz particle size (4000–106 µm) reduced the compressive strength. • Ms additives imparted the lowest compressive strength because of its properties. • Finer Qtz aggregates (4000–106 µm) resulted in a reduced pore volume. [ABSTRACT FROM AUTHOR]