Characterization of Coal Fly Ash for Use in Synthesis of Zeolites

Abstract

Due to the large quantity of fly ash produced during the combustion of coal, it has become necessary to give greater applicability to this residue of low commercial value. The residue contains inorganic oxides which can act on the crystalline structure of zeolites, namely silicon and aluminum oxide. The coal ash was submitted to physical and chemical treatments with the aim of potentiating the silicon and aluminum extraction from the residue. The pure ash and the treated ashes were characterized by: X-ray fluorescence (XRF), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transformation infrared spectroscopy (FTIR). By means of the carried out characterizations it was observed that the treatments were effective for the extraction of aluminosilicates from the matrix. The treatments did not affect the morphology, the crystalline phases and neither the chemical composition of the ashes. Seeing this, the coal ash and its treatments showed to be a precursor for the synthesis of zeolites.