A Novel Eco-Friendly Vanadium Precipitation Method by Hydrothermal Hydrogen Reduction Technology
AbstractIn view of the serious pollution problems caused by the traditional vanadium precipitation process, the eco-friendly technology of hydrothermal hydrogen reduction was first applied to precipitate phase pure vanadium sesquioxide (V2O3) products from stripped pentavalent vanadium (V (V)) solution extracted from vanadium-bearing shale. Thermodynamic analysis demonstrate the method of hydrothermal hydrogen reduction is feasible for precipitating V2O3 from V (V) solution at a suitable pH range, and the reduction should better be carried out at a lower pH under the pH range in which V2O3 can exist stably. The V2O3 products of 99.92% in purity and a high vanadium precipitation percentage of 99.25% were achieved under a facile reaction condition of initial solution pH of 6, reaction temperature of 523 K, H2 partial pressure of 4 MPa and reaction time of 2 h. Based on the analysis of XRD and FE-SEM with EDS for the precipitation products obtained at serial reaction times, the phase transformation mechanism was summarized to serial reductions with the phase transformation of HxVyOz(2z−x−5y)− → NaV2O5 → VO2(H2O)0.5 → VOOH → V2O3. Compared with the two-step traditional method of precipitating vanadium with ammonium salt and roast-reduction (react at above 773 K for more than 3 h) for preparing V2O3, this method only experiences one-step reduction under a green atmosphere of H2 gas with a lower reaction temperature of 523 K and a shorter reaction time of 2h. Therefore, this method for vanadium precipitation is characterized by being eco-friendly, having a short process and being low-energy consumption, which has great significance for the sustainable development of vanadium industry. View Full-Text
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Zhang, G.; Zhang, Y.; Bao, S.; Huang, J.; Zhang, L. A Novel Eco-Friendly Vanadium Precipitation Method by Hydrothermal Hydrogen Reduction Technology. Minerals 2017, 7, 182.
Zhang G, Zhang Y, Bao S, Huang J, Zhang L. A Novel Eco-Friendly Vanadium Precipitation Method by Hydrothermal Hydrogen Reduction Technology. Minerals. 2017; 7(10):182.Chicago/Turabian Style
Zhang, Guobin; Zhang, Yimin; Bao, Shenxu; Huang, Jing; Zhang, Liuhong. 2017. "A Novel Eco-Friendly Vanadium Precipitation Method by Hydrothermal Hydrogen Reduction Technology." Minerals 7, no. 10: 182.
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