A novel approach and zero waste concept for making geopolymer-based bauxite residue tiles

ABSTRACT With the increasing demand for sustainable building materials, researchers have developed geopolymer-based tiles using bauxite residue (BR) and other industrial by-products. This approach supports the zero-waste concept by converting waste from alumina refineries, steel plants, and coal-fired power stations into value-added products. The primary constituents include BR, ground granulated blast furnace slag (GGBS), and fly ash (FA), while manufactured sand (MS) and quarry chips (QC) were used as fillers. A small I-Crete (IC) dosage was incorporated as an admixture to improve overall performance. BR exhibits moderate reactivity compared to conventional binders, and its influence was studied at different replacement levels. The optimum mix was 30% BR, 20% GGBS, and 50% FA, with a filler-to-binder ratio of 1:1.5 and 2% I-Crete (R30G20F50I02). Sodium silicate and sodium hydroxide with 4M concentration were alkaline activators. After 28 days of curing, the developed tiles showed excellent flatness (0.6 mm), perpendicularity (