Preparation of green glass from rice husk ash prepared by microwave technique

Abstract

This research was conducted to develop a process for preparing green glass from rice husk ash using microwave technology. The glass composition was formulated with the following molar ratios: 10SiO2: (50-x)B2O3: 10Na2O: 30ZnO: xCr2O3, where x represents the concentration of chromium oxide (0.00, 0.01, 0.02, 0.03, 0.04, and 0.05 mol%). The glass was melted using a microwave furnace, and various properties of the glass were analyzed, including density, refractive index, light absorption, and color in the CIE L*a*b* system. The results showed that both density and refractive index tended to increase with higher Cr2O3 concentrations, while molar volume tended to decrease inversely with the increasing Cr2O3 concentration. Light absorption in the wavelength range of 200–1,100 nanometers revealed absorption peaks at approximately 430 and 612 nanometers. These peaks were attributed to energy level transitions from 4A2g to 4T1g and 4T2g, respectively.