Lateritic soil geopolymer composites for ceramics and engineering construction applications

Abstract

Characterization of an Amazonian, laterite-doped, kaolinitic soil (LK) or “lateritic soil” and laterite-doped metakaolin (LMK) calcined at two distinct rates, as well as granite-marble (GM) particulate industrial wastes was performed by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray fluorescence (XRF) spectrometry, and particle size and distribution analysis. In addition, an LMK geopolymer (GP) and a lateritic metakaolin-based GP reinforced with granite-marble composite (LMKGP-GM) were tested for water resistance and for mechanical strength. XRD and XRF were used to investigate the composition of the composite materials, while XRD confirmed the formation of GP. Just as in the case of highly reactive commercial metakaolin used in construction, according to this study, lateritic soil-based metakaolin presented similar characteristics. Therefore, it could be used in the development of more sustainable ceramics and construction materials, including the use of GM waste as a reinforcing phase/aggregate. © 2022 The American Ceramic Society.