Synthesis and characterization of geopolymer from bagasse bottom ash, waste of sugar industries and naturally available china clay

Abstract

In this paper, synthesis of geopolymer from bagasse bottom ash and naturally available china clay was studied in order to effectively utilize both these low cost and easily available materials. The ash and china clay activated at 900 °C were grinded in three different proportions as a source material for the synthesis of geopolymers to get SiO2/Al2O3 as 2.5, 3.0 and 3.5. Sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) were used as alkaline medium. XRD revealed that clay activated at 900 °C become highly amorphous and disordered material which resulted good quality geopolymer. Different types of mortars ranging in ratio of polymer to sand were made and the compressive strength was measured. The raw material, geopolymer composites and mortars were characterized by using different analytical techniques including X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning electron microscopy (SEM). Highest compressive strength of geopolymer composite was recorded as 2487 with silica to alumina ratio of 2.5 and for mortar 1947 PSI with geopolymer to sand ratio of 1:1 respectively.