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Yimin Zhang - One of the best experts on this subject based on the ideXlab platform.
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synergistic solvent extraction of vanadium from Leaching Solution of stone coal using d2ehpa and pc88a
Separation and Purification Technology, 2017Co-Authors: Qihua Shi, Yimin Zhang, Jing Huang, Tao Liu, Hong Liu, Luyao WangAbstract:Abstract New extractant and an extractant system are attractive for liquid-liquid extraction. To improve the extraction efficiency and selectivity, the binary extractant system consisting of bis-2-ethylhexyl phosphoric acid (D2EHPA) and 2-ethylhexylphosphonic mono-2-ethylhexyl (PC88A) was explored to separate vanadium (V) via synergism from multi-element sulphuric acid Leaching Solution in this study. The optimal proportion and concentration of extractant was investigated and results demonstrated that the maximum synergistic co-efficient was 1.52 by adjusting the volume ratio to 14:6 (D2EHPA/PC88A) when the extractant concentration was 20% (v/v). Next, the selectivity of the mixture was investigated at different pH values and contact time, which demonstrated better separation of vanadium from primary impurities compared with extraction by D2EHPA or PC88A alone. Furthermore, the Fourier Transform Infrared (FT-IR) spectra were employed to analyse the mechanism of extraction. The results suggested that the cation exchange (P OH bands) and coordination reaction (P O bands) contribute to vanadium extraction, and the structure of extracted complex was proposed. The formation of a dimer between D2EHPA and PC88A was demonstrated. Finally, after multi-stage counter-current extraction and stripping, V2O5 product with a high purity of 99.07% was obtained by oxidation, precipitation and calcination.
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Two-Stage Separation of V(IV) and Al(III) by Crystallization and Solvent Extraction from Aluminum-Rich Sulfuric Acid Leaching Solution of Stone Coal
JOM, 2016Co-Authors: Yimin Zhang, Jing HuangAbstract:To improve separation of V(IV) and Al(III) from aluminum-rich sulfuric acid Leaching Solution of stone coal, the two-stage separation by crystallization and solvent extraction methods have been developed. A co-extraction coefficient (k) was put forward to evaluate comprehensively co-extraction extent in different Solutions. In the crystallization stage, 68.2% of aluminum can be removed from the Solution. In the solvent extraction stage, vanadium was selectively extracted using di-2-ethylhexyl phosphoric acid/tri-n-butyl phosphate from the crystalline mother Solution, followed by H2SO4 stripped efficiently. A V2O5 product with purity of 98.39% and only 0.10% Al was obtained after oxidation, precipitation, and calcination. Compared with vanadium extraction from Solution without crystallization, the counter-current extraction stage of vanadium can be decreased from 6 to 3 and co-extraction coefficient (k) decreased from 2.51 to 0.58 with two-stage separation. It is suggested that the aluminum removal by crystallization can evidently weaken the influence of aluminum co-extraction on vanadium extraction and improve the selectivity of solvent extraction for vanadium.
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separation and recovery of vanadium from a sulfuric acid Leaching Solution of stone coal by solvent extraction using trialkylamine
Separation and Purification Technology, 2016Co-Authors: Xiao Yang, Yimin Zhang, Chun ShenAbstract:Abstract Trialkylamine-N235, diluted with sulfonated kerosene containing tri-butyl phosphate, was used to separate vanadium and impurities as Fe, Al, Mg, K, Ca, P, and Si from a Leaching Solution generated by the sulfuric-acid Leaching of vanadium-containing stone coal. Variations in aqueous pH exhibited good extraction of vanadium at an equilibrium pH of 1.6. Vanadium was successfully extracted by a three-stage countercurrent process using 20% N235 and 5% tri-butyl phosphate at an organic-to-aqueous (A/O) phase ratio of 2:1. The loaded organic was then scrubbed with 0.5 mol/L H 2 SO 4 , and most impurities were scrubbed by three-stage scrubbing. 1.0 mol/L NaOH was used to strip of vanadium from the scrubbed organic Solution at an O/A phase ratio of 2:1, where >99% of vanadium was stripped in three stages. After regeneration by 1.0 mol/L H 2 SO 4 , the regenerated organic phase showed a good performance on vanadium extraction even after 5 cycles. Finally, a process flow sheet was established to recover of vanadium from a sulfuric-acid Leaching Solution of stone coal.
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separation and recovery of sulfuric acid from acidic vanadium Leaching Solution by diffusion dialysis
Separation and Purification Technology, 2012Co-Authors: Yimin Zhang, Jing Huang, Xiaobo Zhu, Yi WangAbstract:Abstract Diffusion dialysis with anion exchange membranes was employed to recover sulfuric acid from acid Leaching Solution generated in vanadium producing process. The effects of flow rate, flow rate ratio, V, Al and Fe ions concentration on the recovery of H 2 SO 4 and metal ions rejection were investigated. The results have proved that sulfuric acid permeates well through the membrane used, while the vanadium ions are efficiently rejected. Over 84% H 2 SO 4 recovery efficiency could be achieved by controlling the flow rate of 0.21 × 10 −3 m 3 /h m 2 , flow rate ratio of 1.1–1.3 at 25 °C. V, Al and Fe ions rejection could reach to 93%, 92% and 85%, respectively.
Xiaoyan Xiang - One of the best experts on this subject based on the ideXlab platform.
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Separation of Mo(VI) and Fe(III) from the acid Leaching Solution of carbonaceous Ni–Mo ore by ion exchange
Hydrometallurgy, 2014Co-Authors: Jun Peng, Xuewen Wang, Mingyu Wang, Changjun Jiang, Xiaoyan XiangAbstract:Abstract The separation of Mo(VI) and Fe(III) from the acid Leaching Solution of carbonaceous Ni–Mo ore by ion exchange was studied. The Leaching Solution was a sulfate Solution with pH 0.68, which contained Mo(VI) 10.63 g/L, Ni(II) 2.38 g/L, Fe(III) 11.42 g/L and so on. Experiments confirmed that Mo(VI) can combine with SO 4 2 − to form heteropoly acids in acid sulfate Solution, the Mo(VI) existing in the Leaching Solution was in the form of the heteropoly acid anions with S/Mo mol ratio 1.7–0.3, which can be adsorbed with resin anion. The molybdenum and nickel were respectively recovered from the Leaching Solution by means of the technological process of direct adsorbing Mo with anion exchange resin D314, purifying with CaCO 3 to remove impurities Fe, Al, Si and P from the effluent under the conditions pH 4.01, temperature 80 °C, stirring for 1 h, and then recovering nickel from the purified Solution using Na 2 CO 3 as the precipitant to produce basic nickel carbonate. It was found that the heteropoly acid anions can excite in the [H + ] range of 0.1–1.0 mol/L and, the optimal pH range for it adsorbed from the Leaching Solution with the resin is 0.30–0.74.
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recovery of vanadium from stone coal acid Leaching Solution by coprecipitation alkaline roasting and water Leaching
Hydrometallurgy, 2012Co-Authors: Xuewen Wang, Mingyu Wang, Yeye Fan, Xiaoyan XiangAbstract:Abstract The recovery of vanadium from stone coal acid Leaching Solution by coprecipitation, alkaline roasting and water Leaching was studied. A method used to recover vanadium from stone coal acid Leaching Solution was developed, and it primarily included vanadium coprecipitation with iron in the Solution, vanadium extraction by alkaline Leaching from the precipitate, and vanadium pentoxide preparation with the alkaline Leaching Solution. Experiments found that the vanadium in stone coal acid Leaching Solution can be effectively enriched in the precipitate obtained by adding 3.64 g NaClO 3 per liter Solution with initial pH 1.73 under stirring for 0.5 h at 95 °C. By roasting the mixture of 25 g of the precipitate with 22.5 g NaOH at 170 °C for 1.0 h, and then water Leaching the roasted mixture at 98 °C for 1.0 h under stirring with L/S ratio of 3.3:1 mL/g, 97.0% of vanadium was extracted from the precipitate. After purifying with MgCl 2 , the vanadium pentoxide with purity 99.3% was obtained by adding NH 4 Cl to precipitate ammonium vanadate from the Solution at pH about 2.0, and then roasting the ammonium vanadate at 520 °C for 2.0 h. The essential components of the coprecipitate are KFe 3 (SO 4 ) 2 (OH) 6 and HNaV 6 O 16 ·4H 2 O.
Chun Shen - One of the best experts on this subject based on the ideXlab platform.
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separation and recovery of vanadium from a sulfuric acid Leaching Solution of stone coal by solvent extraction using trialkylamine
Separation and Purification Technology, 2016Co-Authors: Xiao Yang, Yimin Zhang, Chun ShenAbstract:Abstract Trialkylamine-N235, diluted with sulfonated kerosene containing tri-butyl phosphate, was used to separate vanadium and impurities as Fe, Al, Mg, K, Ca, P, and Si from a Leaching Solution generated by the sulfuric-acid Leaching of vanadium-containing stone coal. Variations in aqueous pH exhibited good extraction of vanadium at an equilibrium pH of 1.6. Vanadium was successfully extracted by a three-stage countercurrent process using 20% N235 and 5% tri-butyl phosphate at an organic-to-aqueous (A/O) phase ratio of 2:1. The loaded organic was then scrubbed with 0.5 mol/L H 2 SO 4 , and most impurities were scrubbed by three-stage scrubbing. 1.0 mol/L NaOH was used to strip of vanadium from the scrubbed organic Solution at an O/A phase ratio of 2:1, where >99% of vanadium was stripped in three stages. After regeneration by 1.0 mol/L H 2 SO 4 , the regenerated organic phase showed a good performance on vanadium extraction even after 5 cycles. Finally, a process flow sheet was established to recover of vanadium from a sulfuric-acid Leaching Solution of stone coal.
Jing Huang - One of the best experts on this subject based on the ideXlab platform.
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synergistic solvent extraction of vanadium from Leaching Solution of stone coal using d2ehpa and pc88a
Separation and Purification Technology, 2017Co-Authors: Qihua Shi, Yimin Zhang, Jing Huang, Tao Liu, Hong Liu, Luyao WangAbstract:Abstract New extractant and an extractant system are attractive for liquid-liquid extraction. To improve the extraction efficiency and selectivity, the binary extractant system consisting of bis-2-ethylhexyl phosphoric acid (D2EHPA) and 2-ethylhexylphosphonic mono-2-ethylhexyl (PC88A) was explored to separate vanadium (V) via synergism from multi-element sulphuric acid Leaching Solution in this study. The optimal proportion and concentration of extractant was investigated and results demonstrated that the maximum synergistic co-efficient was 1.52 by adjusting the volume ratio to 14:6 (D2EHPA/PC88A) when the extractant concentration was 20% (v/v). Next, the selectivity of the mixture was investigated at different pH values and contact time, which demonstrated better separation of vanadium from primary impurities compared with extraction by D2EHPA or PC88A alone. Furthermore, the Fourier Transform Infrared (FT-IR) spectra were employed to analyse the mechanism of extraction. The results suggested that the cation exchange (P OH bands) and coordination reaction (P O bands) contribute to vanadium extraction, and the structure of extracted complex was proposed. The formation of a dimer between D2EHPA and PC88A was demonstrated. Finally, after multi-stage counter-current extraction and stripping, V2O5 product with a high purity of 99.07% was obtained by oxidation, precipitation and calcination.
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Two-Stage Separation of V(IV) and Al(III) by Crystallization and Solvent Extraction from Aluminum-Rich Sulfuric Acid Leaching Solution of Stone Coal
JOM, 2016Co-Authors: Yimin Zhang, Jing HuangAbstract:To improve separation of V(IV) and Al(III) from aluminum-rich sulfuric acid Leaching Solution of stone coal, the two-stage separation by crystallization and solvent extraction methods have been developed. A co-extraction coefficient (k) was put forward to evaluate comprehensively co-extraction extent in different Solutions. In the crystallization stage, 68.2% of aluminum can be removed from the Solution. In the solvent extraction stage, vanadium was selectively extracted using di-2-ethylhexyl phosphoric acid/tri-n-butyl phosphate from the crystalline mother Solution, followed by H2SO4 stripped efficiently. A V2O5 product with purity of 98.39% and only 0.10% Al was obtained after oxidation, precipitation, and calcination. Compared with vanadium extraction from Solution without crystallization, the counter-current extraction stage of vanadium can be decreased from 6 to 3 and co-extraction coefficient (k) decreased from 2.51 to 0.58 with two-stage separation. It is suggested that the aluminum removal by crystallization can evidently weaken the influence of aluminum co-extraction on vanadium extraction and improve the selectivity of solvent extraction for vanadium.
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separation and recovery of sulfuric acid from acidic vanadium Leaching Solution by diffusion dialysis
Separation and Purification Technology, 2012Co-Authors: Yimin Zhang, Jing Huang, Xiaobo Zhu, Yi WangAbstract:Abstract Diffusion dialysis with anion exchange membranes was employed to recover sulfuric acid from acid Leaching Solution generated in vanadium producing process. The effects of flow rate, flow rate ratio, V, Al and Fe ions concentration on the recovery of H 2 SO 4 and metal ions rejection were investigated. The results have proved that sulfuric acid permeates well through the membrane used, while the vanadium ions are efficiently rejected. Over 84% H 2 SO 4 recovery efficiency could be achieved by controlling the flow rate of 0.21 × 10 −3 m 3 /h m 2 , flow rate ratio of 1.1–1.3 at 25 °C. V, Al and Fe ions rejection could reach to 93%, 92% and 85%, respectively.
Xuewen Wang - One of the best experts on this subject based on the ideXlab platform.
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Separation of Mo(VI) and Fe(III) from the acid Leaching Solution of carbonaceous Ni–Mo ore by ion exchange
Hydrometallurgy, 2014Co-Authors: Jun Peng, Xuewen Wang, Mingyu Wang, Changjun Jiang, Xiaoyan XiangAbstract:Abstract The separation of Mo(VI) and Fe(III) from the acid Leaching Solution of carbonaceous Ni–Mo ore by ion exchange was studied. The Leaching Solution was a sulfate Solution with pH 0.68, which contained Mo(VI) 10.63 g/L, Ni(II) 2.38 g/L, Fe(III) 11.42 g/L and so on. Experiments confirmed that Mo(VI) can combine with SO 4 2 − to form heteropoly acids in acid sulfate Solution, the Mo(VI) existing in the Leaching Solution was in the form of the heteropoly acid anions with S/Mo mol ratio 1.7–0.3, which can be adsorbed with resin anion. The molybdenum and nickel were respectively recovered from the Leaching Solution by means of the technological process of direct adsorbing Mo with anion exchange resin D314, purifying with CaCO 3 to remove impurities Fe, Al, Si and P from the effluent under the conditions pH 4.01, temperature 80 °C, stirring for 1 h, and then recovering nickel from the purified Solution using Na 2 CO 3 as the precipitant to produce basic nickel carbonate. It was found that the heteropoly acid anions can excite in the [H + ] range of 0.1–1.0 mol/L and, the optimal pH range for it adsorbed from the Leaching Solution with the resin is 0.30–0.74.
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recovery of vanadium from stone coal acid Leaching Solution by coprecipitation alkaline roasting and water Leaching
Hydrometallurgy, 2012Co-Authors: Xuewen Wang, Mingyu Wang, Yeye Fan, Xiaoyan XiangAbstract:Abstract The recovery of vanadium from stone coal acid Leaching Solution by coprecipitation, alkaline roasting and water Leaching was studied. A method used to recover vanadium from stone coal acid Leaching Solution was developed, and it primarily included vanadium coprecipitation with iron in the Solution, vanadium extraction by alkaline Leaching from the precipitate, and vanadium pentoxide preparation with the alkaline Leaching Solution. Experiments found that the vanadium in stone coal acid Leaching Solution can be effectively enriched in the precipitate obtained by adding 3.64 g NaClO 3 per liter Solution with initial pH 1.73 under stirring for 0.5 h at 95 °C. By roasting the mixture of 25 g of the precipitate with 22.5 g NaOH at 170 °C for 1.0 h, and then water Leaching the roasted mixture at 98 °C for 1.0 h under stirring with L/S ratio of 3.3:1 mL/g, 97.0% of vanadium was extracted from the precipitate. After purifying with MgCl 2 , the vanadium pentoxide with purity 99.3% was obtained by adding NH 4 Cl to precipitate ammonium vanadate from the Solution at pH about 2.0, and then roasting the ammonium vanadate at 520 °C for 2.0 h. The essential components of the coprecipitate are KFe 3 (SO 4 ) 2 (OH) 6 and HNaV 6 O 16 ·4H 2 O.