Grinding of Biogenic Silica

The article examines temperature conditions for the thermal synthesis of silica from rice husk and different conditions for subsequent milling. In the study, the following methods were used: elemental analysis, x-ray diffraction analysis, petrographic analysis, electron and atomic force microscopy, differential scanning calorimetry, and laser granulometry. The occurrence of silica was detected at about 650°C; its structure remained stable during pyrolysis and subsequent thermal treatment in the presence of air. Following thermal treatment at 1000 – 1100°C, cristobalite remained the predominant phase. The milling of thermal treatment products involved a significant loss of process efficiency due to the cellular structure of aggregates and their plastic failure.