Abstract:

Cubic Sb₂O₃ was prepared by vacuum heating method using orthorhombic Sb₂O₃ obtained by wet process as raw material.The effects of the system pressure，heating temperature and heating time on Sb₂O₃ crystal form and grain size were investigated by X-ray diffraction（XRD） and scanning electron microscopy（SEM）.The results showed that Sb₂O₃ was gradually changed from orthorhombic crystal to cubic crystal when the heating temperature was increased.When the heating temperature was rised to 450 ℃，some of cubic Sb₂O₃ began to change to orthorhombic Sb₂O₃ again.The agglomeration degree and average particle size of the sample were increased with increasing heating temperature.With the decrease of the system pressure and the extension of the heating time，Sb₂O₃ was gradually transformed from orthorhombic crystal to cubic crystal.However，the decrease of the system pressure would increase the degree of sample agglomeration and the average particle size of the sample.With the prolonged heating time，the average particle size of the sample was gradually increased.

Key words: Sb₂O₃, vacuum heating method, cubic crystal