Abstract Dielectric properties and heating characteristics of stibnite concentrate and pure antimony compounds were assessed. Stibnite concentrate and Sb2S3 have high dielectric properties and heating efficiency while Sb2O4 and Sb2O3 are relatively low. Sb2O5 is high from 25 to 300 °C and sharply decreases due to decomposition. Microwave heating process in air has four stages and the roasting process appears at the third stage with corresponding phase changes as Sb2S3 → Sb2O3 → Sb2O5 → Sb2O4. XRD and SEM-EDS results show that Sb2S3 is thoroughly oxidized to Sb2O3 before 400 °C and Sb2O3 is further oxidized into Sb2O4 above 500 °C. Sb2O4 reacts with Fe2O3 above 800 °C to form FeSbO4. Microwave heating mechanism shows FeS2 is the main absorber from 25 to 300 °C, and Sb2S3 was the main absorber above 331.6 °C, indicating theoretical basis for microwave selective roasting stibnite concentrate to produce antimony oxide powder.

中文翻译：

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锑精矿吸波特性及微波焙烧机理的基础研究

摘要 评估了辉锑矿精矿和纯锑化合物的介电性能和加热特性。辉锑矿精矿和 Sb2S3 具有较高的介电性能和加热效率，而 Sb2O4 和 Sb2O3 相对较低。Sb2O5 在 25 到 300 °C 范围内很高，并且由于分解而急剧下降。空气中的微波加热过程有四个阶段，焙烧过程出现在第三阶段，相应的相变为 Sb2S3 → Sb2O3 → Sb2O5 → Sb2O4。XRD 和 SEM-EDS 结果表明 Sb2S3 在 400°C 之前被彻底氧化为 Sb2O3，而 Sb2O3 在 500°C 以上被进一步氧化为 Sb2O4。Sb2O4 在 800 °C 以上与 Fe2O3 反应生成 FeSbO4。微波加热机理表明FeS2是25-300℃的主要吸收剂，Sb2S3是331.6℃以上的主要吸收剂，