(1. 中南大學(xué) 資源加工與生物工程學(xué)院，長沙 410083；
2. 湘潭大學(xué) 化工學(xué)院，湘潭 411105)
摘 要: 通過微波空白焙燒−酸浸提釩與傳統(tǒng)加熱焙燒−酸浸提釩和直接酸浸提釩的對比實(shí)驗(yàn)，考察H2SO4用量和浸出時(shí)間對石煤中釩浸出的影響。結(jié)果表明：石煤在700 ℃下微波焙燒60 min，H2SO4用量為礦樣質(zhì)量的22%，浸出溫度為90 ℃時(shí)，V2O5浸出率達(dá)到83.50%，比傳統(tǒng)加熱焙燒−酸浸提釩和直接酸浸的浸出率提高約30%。通過對焙燒熟料酸浸和直接酸浸時(shí)Al2O3 浸出率的分析發(fā)現(xiàn)，V2O5浸出率與Al2O3 浸出率呈正相關(guān)性。結(jié)合礦物晶體構(gòu)造與微波加熱原理，探討了微波焙燒改善酸浸提釩的機(jī)理，認(rèn)為微波焙燒可破壞含釩云母的晶體結(jié)構(gòu)，是提高V2O5浸出率的主要原因。
關(guān)鍵字: 石煤；五氧化二釩；微波焙燒；酸浸工藝
extraction of vanadium from stone coal
（1. School of Mineral Processing and Bioengineering, Central South University, Changsha 410083, China;
2. College of Chemical Engineering, Xiangtan University, Xiangtan 411105, China）
Abstract:Compared with the conventional roasting-acidic leaching procedure and acidic leaching process of raw stone coal, the microwave roasting-acidic leaching technique for extraction of vanadium from stone coal was developed, and the effects of H2SO4 dosage and leaching time on vanadium extraction were investigated. The results show that the leaching rate of V2O5 reaches up to 83.5% when the tested sample is microwave roasted (without any additive) at 700 ℃ for 60 min, the dosage of sulfuric acid is 22% of V2O5 leaching at 90 ℃. The leaching rate is improved by about 30%, more than that obtained from the conventional roasting or acidic leaching of raw stone coal under the same leaching conditions. The positive correlation between the leaching rate of V2O5 and Al2O3 is found out by leaching V2O5 and Al2O3 from both the roasted samples and raw stone coal. Based on the minerals crystal constitution and the characteristics of microwave roast, the mechanism on improving the leaching rate of V2O5 by microwave roasting was discussed. It is indicated that the breakage of the minerals crystal constitution resulted from microwave roasting is the key factor of affecting the improvement of V2O5 leaching rate.
Key words: stone coal; vanadium pentoxide; microwave roasting; acidic leaching technique
