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With the development of science and technology, vanadium applications continue to expand, more and more high purity requirements of vanadium products, the preparation of high purity refined vanadium technology is necessary. Vanadium in Stone Coal, phosphorus, silicon impurities affect the quality of refined vanadium. In this paper, stone coal vanadium extraction process of ion exchange analytical solution for the raw material liquid behavior for the Stone Coal vanadium ion exchange process in phosphorus, silicon, magnesium salt precipitation from the solution of sodium vanadate depth phosphorus removal, silicon and metavanadate Ammonium mechanism of crystallization, prepared high purity V205. Analysis of the mechanism the dephosphorization, silicon process, and studied the influence of the magnesium salt added in an amount, pH, temperature, time, and other factors on the dephosphorization, silicon effects. Experimental results show that: the weak alkaline conditions, the magnesium salt method can effectively remove the vanadium sodium, phosphorus, silicon, phosphorus removal rate of more than 95% silicon removal rate reached more than 96%, but will also effectively remove vanadate solution of sodium impurity elements such as Fe, As, last V205 recovery rate of 94% or more. Best phosphorus removal, silicon process conditions: temperature 45 ℃, purge time 40 min, added mass fraction of 20% of the amount of magnesium chloride with raw liquid volume ratio of 0.12:1, pH = 9.5. Net after the filtrate was added at 50 ℃ the ammonium salt Shen vanadium, ammonium metavanadate obtained in 500 ℃ muffle furnace under calcination 2H finally obtained vanadium pentoxide product quality reaches 99.91% or more. The crystallization process is an important part of the fine vanadium extraction, crystallization process itself also has the role of Impurity. Further study the crystallization process of ammonium metavanadate investigated plus ammonium coefficient vanadium concentration, pH of the reaction, stirring intensity, the the plus ammonium way, the crystallization temperature and time, and other factors Shen of Vanadium rate and ammonium metavanadate crystal morphology the impact. The experimental results show that the the best Shen vanadium conditions: plus ammonium coefficient 1.3, vanadium concentration of 80g / L, pH = 9.5, stirring intensity 300r/min ammonium salt was added in two, the reaction temperature of 45 ° C, Shen vanadium time 30min , Shen vanadium do not need to stand for direct filtration, was washed with 2% NH4Cl after cold. Ammonium metavanadate obtained crystals were analyzed by scanning electron microscopy, diamond structure having a regular crystal coarse uniform, smooth surface integrity, reducing impurity contamination, calcined at 500 ℃ in a muffle furnace for 2 h, the resulting vanadium pentoxide The product also has a regular diamond structure, smooth surface, uniform size, angular, less polluting impurities, product quality has reached 99.95%.
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