Studies on the Application of Eco-friendly Geopolymer as a Binder for Refractory Castables

Abstract

In recent years, there have been strong demands for the processing of no cement refractory castable to overcome on the high cost of HAC and to improve the thermal resistance of castables at high temperature applications. They have received increased attention because of their unique characteristics. Among the established no-cement castable ceramic materials are very fine powder material as hydratable alumina, alpha bonded alumina, very fine reactive MgO powder, colloidal silica, etc, used as a binder material. However, the cost of currently available low and no-cement castables is relatively high. Geopolymers are expected to be beneficial and important for consideration in new the refractory applications. However, little work has been done to investigate the use of geopolymer instead of calcium aluminate cement as a binder in refractory castables. This work investigates and studies the effect of replacement of HAC with one-part geopolymer slag on phase composition, microstructure, physical, mechanical, and thermal properties of produced refractory castables. The outcomes of the present study depict that refractory castables can be designed with 25% replacement of HAC with one-part geopolymer without a significant change in phase composition, microstructure, physical and mechanical properties.