Chemical and physical characterization of boiler ash from palm oil industry waste for geopolymer composite

Abstract

The characterizations of boiler ash waste from waste of palm oil industry were performed. The boiler ash was obtained from the boiler in the palm oil processing factory. The chemical and physical characterization has been analyzed using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), particle size distribution, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). From the XRF analysis, the major component of boiler ash is silica oxide (SiO2), followed by calcium oxide (CaO) and ferum oxide (Fe2O3) In order to produce geopolymer, the raw material needs to contain enough SiO2 and aluminium oxide (Al 2O3). However, the content of Al203, is only 3.7% but it contained high amount o f SiO2 (40.60%) and CaO which may influence the strength ofhe geopolymer. The median particle size of boiler ash was comparable with fly ashes, morphology of boiler ash showed irregular particle size and shape. The surface particle of boiler ash look similar with calcined kaolin but no plate like stmcture was obsewed. Hence, we believe that this material has a potential use as raw material for geopolymer production.