Comparison of original and washed pure sugar cane bagasse ashes assupplementary cementing materials

Abstract

[EN] The objective of this study was to evaluate the effects of potassium extraction on the pozzolanicity of sugar cane bagasse ash (SCBA), with the aim of producing reactive ash for use in cementitious composites. The sugar cane bagasse ashes were produced at 600 °C for 60 min, with a heating rate of 4 °C/min. The ashes were then ground and washed for potassium extraction. In order to assess the ash behaviour before and after potassium extraction, the following procedures were performed: energy-dispersive spectroscopy (EDS), loss on ignition (LOI), particle size distribution, x-ray powder diffraction (XRD), x-ray diffraction in calcium hydroxide paste, analysis of lime fixation by thermogravimetry, and evaluation of pozzolanic reactivity analyses. Results show that the extraction of potassium, increases the concentration of silica causing a greater pozzolanic reactivity of the ashes.