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This paper presents a clean, efficient, low-cost stone coal vanadium extraction process, the process including blank roasting - pressurized alkaline leaching - desilication - extraction - Shen vanadium - the calcination process. The Process somewhere refractory stone coal vanadium ore eventually vanadium recovery was 82.14%, 98.5% purity V2O5. Proved low reagent consumption of the process vanadium extraction, vanadium high yield, fast response, less waste emissions, the production of qualified products. Thesis, the content and conclusions are as follows: the process for roasting - Atmospheric alkali extraction of vanadium extraction of vanadium from stone coal vanadium ore in the presence of a base consumption leaching time and high impurity content of the leaching solution, this study uses pressurized alkaline leaching of stone coal vanadium mine calcine. The test examines the amount of alkali, liquid to solid ratio, leaching time, the anion type and concentration factors of vanadium leaching. The results show that, using mine weight of 3.5% NaOH, the ratio of liquid to solid 1.5 / 1,180 ℃ insulation 2 hours, 86% of vanadium leaching rate, leaching solution of vanadium silicon quality concentration ratio to 0.65, the pH of the leaching solution about 11.4, and Crafts I the the liquid fill alkali cycle returns after leaching SO42-, C1-accumulation concentration not exceeding 10,7 g / L, does not affect the leaching effect. Pressurized alkaline leaching vanadium leaching rate, impurities leaching rate is low, provides a new way for the stone coal vanadium. Depending on the nature of the silicon, the pH of the solution is adjusted to 9.0-8.5, so that most of the silicon is precipitated in solid H4SiO4 precipitate the stub colloidal H4SiO4 Coagulation removed by precipitation, and ultimately achieve the purpose of efficient separation of vanadium silicon. Specific process: First, using H2SO4 to adjust the pH value of the leaching solution of stone coal to 9.0 to 8.5, heated to 90-95 ° C, insulation 1 ~~ 2min, transparent colorless to solid to liquid at room temperature; then put into the solution quality of 0.1% of the A12 ( S04) 3.18 H20, 50 ℃ for 30min, filtered, and complete the entire silicon removal process. Final vanadium yield of 98.16%, in addition to silicon rate reached 97.48%, vanadium silicon get good separation. Silicon vanadium ion nature shows that when the solution 7.0 lt; pH lt; 9.0 when, vanadium easy to be extracted, and vanadium silicon ions differences in the nature of large separation easy analysis under alkaline conditions. Select organic phase composition: 15% N263 10% TBP 75% sulfonated kerosene, calculated in accordance with the organic phase of the extraction work capacity (CV2O5 = 24g / L) selective extraction compared three countercurrent extraction, the raffinate V205 concentration lower than 0.01g / L, the V205 concentration of the organic phase is about 24g / L, the SiO2 concentration of about 0.1g / L, the loaded organic phase washed with pure water 1, and can be used for stripping. The mechanism of extraction: 3 (R4N) Cl V3O93-= (R4N) 3V3O9 3Cl-. Stripping NaOH NaCl system, concentrations were 0.7,2.5 mol / L, compared with the O / A = 5/1, test load concentration of the organic phase V205 to 25.401g / L stripping. The three stage countercurrent stripping, the vanadium stripping rate reached 99.34%, the concentration of the stripping solution of V2O5 as 126.163g / L value of 10.2, the pH of the stripping solution, the organic phase residual V2O5 concentration to 0.167 g / L. Stripping, while the following two reactions: 2 (R4N) 3V3O9 6OH 6Cl-= 6R4NCl 3V2O74-H2O at (R4N) 3V3O9 3Cl-= 3R4NC1 V3O93-In this paper, using NH4Cl Shen vanadium. Shen vanadium process: the stripping solution pH was adjusted to 9.0 by adding acid first, then take K ammonium = 1.47, adding solid of NH4Cl, stirring at 45 ℃ for 1 h, the last allowed to stand at room temperature (25 ℃) for 4 hours, the mother liquor V205 0.321 g / L, Shen the Vanadium rate reached 99.73%. Get NH4VO3 drying, calcination get the V205 the quality meet the national standard 98.5% grade. The advantage of the process: \, equipment corrosion requirements. The test conclusions show that the technology is reliable, economic and technical indicators, and good prospects for industrial applications.
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