淅川石煤钒矿提取技术的研究

STUDIES ON EXTRACTION OF VANADIUM FROM XICHUAN STONE COAL

石煤提钒技术关键是钒的氧化和转化。浙川石煤中钒主要有V^(3+)和V^(4+)形式存在,以类质同象取代粘土矿物二八面体中Al^(3+)。钒的价态分布研究表明,低温时有机质和黄铁矿决定了钒的价态,在370℃(风化样)或490℃(原样)V^(3+)全部氧化至V^(4+);高于800℃V^(4+)不再氧化至V^(5+),反应处于动态平衡,此时ηV^(5+)达91％。同时讨论了氯化钠在提钒过程中的氧化和转化作用,石煤钠盐氧化焙烧提钒的最佳条件:矿:盐=100:15,800℃,30分钟,η_培为67.4％。实验表明,焙烧气氛对钒转化有很大影响,氧化—氯化焙烧技术提高η_培6％。

Vanadium-bearing stone coal of Xichuan is a new vanadium resource, the extraction of V2O5 from the coal depends on both oxidation and transformation of vanadium. V in the coal mainly exists in two oxidation states: V3+and V4+ ,as an isomorphic form,occupies the sites of A13+which exists in the bi-octahedron of illite clay mineral. The distribution of valency of V shows that organic matter and pyrite determine V valency at low tempera-tures,about 490℃ V3+in original coal completely oxidized to V4+ ;above 500℃,no more V4+is oxidized to V5+ : the reaction was in a dynamic equilibrium condition,in which 91% of V is oxidized to V5+. The oxydation and transformation roles of NaCl in the recovery of V2O5 from the coal were discussed, the best conditions for salt and stone coal roasting are:ore : NaCl =100 : 15 by weight,temperature 850℃ for half hour ηroass reaches 67. 4%. The atmosphere composition in the roasting process plays an important role in transformation in stone coal , the results of experiments show that the oxidation-chlorination roasting technique can increase ηroass by 6. 0%.