The aim of the present paper is to evaluate the potential conversion of a chemically- and thermally-modified sodium-rich calcium alumino-silicate material (SRCAS, the engineering product of a treated waste product from the aluminium industry, spent pot-liners) into a new binder. Thus, great savings could be made due to the dual nature of SRCAS both as a mineral admixture and as a clinker-free binder. This paper presents the results of an investigation into the use of appropriate activators and/or favourable activation conditions (humidity, temperature) to further improve the binding properties of SRCAS. Effective activators (type and concentration), temperature of activation, and water-to-binder ratio were evaluated. Experimental results show that SRCAS has been easily transformed into a binder from which different paste, mortar, and concrete have been successfully fabricated and tested. High early-strength paste, mortar, and concrete have been obtained after less than 24 hours and some pastes have resulted in compressive strengths of 90MPa after the same activation time.
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