Reprocessing of coal fly ash through desilication and dealumination methods for the synthesis of silica and alumina nanoparticles

<p dir="ltr">This research discusses the extraction of Si and al through various methods for the synthesis of silica and alumina nanoparticles. To extract Si from CFA, three methods were employed: (1) NaOH leaching, (2) H₂SO₄ leaching followed by NaOH leaching and (3) Thermochemical treatment of CFA followed by NaOH leaching. In order to remove Al from the coal fly ash, four methods were employed: (1) H₂SO₄ leaching, (2) NaOH leaching followed by H₂SO⁴ leaching, (3) Thermochemical treatment and (4) NaOH leaching followed by thermochemical treatment.</p><p dir="ltr">After Si and Al extraction, sodium silicate and aluminium sulphate solutions were formed, from which silica and alumina nanoparticles were produced, respectively.</p>