粗四氯化钛有机物精制除钒尾渣提钒技术

从四氯化钛有机物精制除钒尾渣中提钒并制备V2O5产品，研究了精制除钒尾渣焙烧温度、浸出剂加入量、液固比、浸出温度、浸出时间对尾渣中钒转化和溶出率的影响。结果表明，焙烧温度大于600℃时，可高效脱除精制除钒尾渣中的碳和氯(?0.1%)，且低价钒被氧化为高价，钒主要以V2O5形式存在。对焙烧后的尾渣以Na2CO3水溶液为浸出剂，液固比6 mL/g及80℃下浸出60 min，钒浸出率为85.5%，浸出液仅含少量Si, Al, Ti杂质，以NH4+:V=2.5:1(摩尔比)直接加铵盐沉钒，得到NH4VO3，经干燥、煅烧制得V2O5产品，可满足99级粉钒指标要求，全流程钒收率为75%。

Vanadium extraction from vanadium removal tailings of crude titanium tetrachloride organic refining

In the process of preparing titanium tetrachloride by chlorination technology, vanadium oxychloride and titanium tetrachloride will be extracted and condensed at the same time. Because of the close boiling point, aluminum powder or organic substance is used to remove vanadium oxychloride from titanium tetrachloride in order to prepare titanium products such as sponge titanium, titanium dioxide and so on. The tailing produced by organic refining was a kind of high-quality raw material for vanadium extraction due to the high content of V2O5 (20wt%), and the impurity element is relatively few. In view of the extraction of vanadium from the tailing obtained by organic refining of titanium tetrachloride and the preparation of vanadium pentoxide product, the roasting temperature, the amount of leaching agent, the ratio of liquid to solid and the leaching temperature were studied. Furthermore, the effect of leaching time on the conversion rate and dissolution rate of vanadium in the tailing were studied respectively. The results showed that when calcination temperature was higher than 600℃, carbon and chlorine could be removed efficiently (<0.1%). Vanadium mainly existed in the form of vanadium pentoxide in the slag after roasting. The roasted slag was leached with sodium carbonate aqueous solution, the ratio of liquid to solid was 6 mL/g, the leaching rate of vanadium was 85.5% at 80℃ for 60 min. The leaching solution contained only a small amount of Si, Al, Ti, P impurities, which was suitable to precipitate vanadium product directly. Ammonium metavanadate was prepared by addition of ammonium salt with NH4+:V=2.5:1 (molar ratio), and stirring at room temperature for 120 min, after filtering, washing, drying and calcining to obtain vanadium pentoxide. The chemical composition of vanadium pentoxide can fully meet the requirement of grade 99 powder vanadium. The vanadium yield of the whole process was 75%.