Properties of Aluminosilicate Glasses Prepared by Red Mud with Various [Al₂O₃]/[CaO] Mass Ratios

【摘要】 By introducing other oxide materials（SiO₂, Al₂O₃, CaO） into the red mud, all materials were melted into aluminosilicate glasses. On the basis of 17.2Fe₂O₃-5.7CaO-18.2Al₂O₃-50SiO₂-5.9Na₂O-3TiO₂ system glasses, [Al₂O₃]/[CaO] mass ratio changed further. For each sample, the assignment of IR absorption bands for aluminosilicate glasses was investigated by Fourier transform infrared spectroscopy and the glasstransition temperature and high temperature molten state were studied by differential scanning calorimetry. According to X-Ray diffraction and differential scanning calorimetry, the behavior of crystallization was analyzed. The results show that the glass structures of three-dimensional network are depolymerized and the amount of non-bridging oxygens increases gradually with network modifier CaO replacing network intermediate Al₂O₃ when [Al₂O₃]/[CaO] ratio of aluminosilicate glass decreases from 4.05 to 0.66, resulting in decreasing density, melting temperature, crystallization peak temperature and glass-transition temperature. As [Al₂O₃]/[CaO] mass ratio decreases, the concentration of crystallized phase maghemite（γ-Fe₂O₃） will increase which provides the possibility for production of black glass-ceramic further.更多还原

【Abstract】 By introducing other oxide materials（SiO₂, Al₂O₃, CaO） into the red mud, all materials were melted into aluminosilicate glasses. On the basis of 17.2Fe₂O₃-5.7CaO-18.2Al₂O₃-50SiO₂-5.9Na₂O-3TiO₂ system glasses, [Al₂O₃]/[CaO] mass ratio changed further. For each sample, the assignment of IR absorption bands for aluminosilicate glasses was investigated by Fourier transform infrared spectroscopy and the glasstransition temperature and high temperature molten state were studied by differential scanning calorimetry. According to X-Ray diffraction and differential scanning calorimetry, the behavior of crystallization was analyzed. The results show that the glass structures of three-dimensional network are depolymerized and the amount of non-bridging oxygens increases gradually with network modifier CaO replacing network intermediate Al₂O₃ when [Al₂O₃]/[CaO] ratio of aluminosilicate glass decreases from 4.05 to 0.66, resulting in decreasing density, melting temperature, crystallization peak temperature and glass-transition temperature. As [Al₂O₃]/[CaO] mass ratio decreases, the concentration of crystallized phase maghemite（γ-Fe₂O₃） will increase which provides the possibility for production of black glass-ceramic further.更多还原