Fabrication of Alkali Borosilicate Glass using Fly Ash from Industrial Waste

The possibility of using industrial fly ash waste as a silica source for alkali borosilicate glass was investigated. The compositions of fly ash were analyzed by energy dispersive x-ray spectrometer (EDXRF). Alkali borosilicate glasses were prepared from the fly ash in formula (80-x)B2O3:20Na2O:xSiO2 (where x = 20, 25, 30, 35, 40 and 45% by weight) by melt quenched technique. The result found that the main compositions of flyash are SiO2, CaO, Al2O3 and Fe2O3. The yellow colors of glasses were obtained due to Fe composition in glass matrix, correspond with absorption spectra from uv-visible spectrophotometer. The peaks around 380 and 450 nm were attributed to Fe3+ and around 1,000 nm due to Fe2+ ions. Their densities and refractive indices were increased with increasing of fly ash concentration.