Synthesis of a two-part geopolymer from red mud and silica fume

Abstract

In this present study, the development of a two-part geopolymer from waste red mud (RM) and silica fume (SF) by alkali activator is examined. The influence of silica fUme addition, alkali concentration, curing duration are studied. The compressive strength of geopolymers has been achieved 0.8 MPa to 8 MPa with varying different compositions and synthesis parameters. The optimum RM/SF ratio is 60/40, the optimum solid/solution ratio is 1.8 g-mL-1 or 2 g-mL-1, and the optimum Na2SiO3/NaOH ratio is 0.5 day for 28 days curing time. The incorporation of iron in the geopolymer matrix contributes to geopolymerization. The study suggests that the produced geopolymer can be used as cementitious materials for making pavement and other valuable constructional materials. This procedure will be environment friendly and cheaper also.