Investigating the hydration of deflocculated calcium aluminate cement-based binder with catalyst waste

Abstract

The hydration of the binder, consisting of calcium aluminate cement (CAC) with Al2O3[70% and with or without the additives of the FCC catalyst waste and polycarboxylate deflocculant Castament FS-20, is investigated. The methods of calorimetry, thermal analysis, XRD, electrical conductivity, SEM, as well as ultrasonic wave velocity measuring and bending strength evaluation are used. The results of the investigation show that the FCC catalyst as well as polycarboxylate deflocculant, are active additives, influencing the CAC binder’s hydration process. In the structure of the hardened binders, certain amounts of unhydrated CAC minerals, CA, and CA2, and the hydration products, such as CAH10, C2AH8 and the amorphous AH3, are found. However, in the binder with a deflocculant, there are smaller amounts of CAH10 and the amorphous AH3, though the amount of C2AH8 is higher than that in the binder without a deflocculant additive. It has been found that in the case, when the FCC catalyst and deflocculant are simultaneously used, the FCC catalyst produces a positive effect on the formation of the CAC binder’s structure, increasing its mechanical strength. The results obtained in this article allow to predict that the FCC catalyst and deflocculant simultaneously used as the additives to the CAC binder, will enable to control the hydration process of the binder.