Research on the Influence of Calcination Temperature on the Content of Free Silicon Dioxide in Dust

In order to verify the oxidation of silicon to silicon dioxide during the calcination process of silica containing dust, silicon powder and monocrystalline silicon were calcined at different temperatures. The sample was analyzed using Fourier transform infrared spectroscopy (FTIR) and compared with the FTIR spectrum of the silica standard. The results show that the antisymmetrical stretching vibration, symmetrical stretching vibration and bending vibration absorption peak of Si-O-Si were obviously in the FTIR spectra of silicon powder and monocrystalline silicon calcined at 750oC. The positions of those absorption peaks correlate broadly with the absorption peaks of standard silica. It is concluded that when the calcination temperature was above 750oC, elemental silicon would be oxidized to silica at different levels, which would cause a higher silica content detected in dust.