The study of silica from pumice was done by extraction method using NaOH, H2SO4, and HCl. Powder of pumice before extraction was calcined at 450oC for 4 hours. The extraction powder was calcined at 800 °C for 3 hours. The powder before and after the extraction were characterized by XRD and SEM-EDS. Sample also characterized by DTA-TGA analysis before extraction and after extraction was analyzed by TEM. XRD pattern powder of pumice dominated by amorphous silica. The results have been confirmed with SEM-EDS showing that the silica content has the highest percentage, ie 65.88% for the sample before extraction and 78.95% for the sample after extraction. From the TEM observation it shows spherical particles, with particle size of 5.8 ± 0.2 nm. DTA-TGA analysis for pumice powder shows the occurrence of endotherm and exothermic events accompanied by mass shrinkage along with warming temperature rise.
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