JOM
·
2016
·Vol. 69
·期 10
·1950-1957
·
IF 1.798
Shi Qihua,Zhang Yimin,Liu Tao,Huang Jing,Liu Hong
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 H 2 SO 4 stripped efficiently. A V 2 O 5 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.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2024
·
IF 4.1
Tian Zhou,Zhangnan Xu,Nianben Zheng,Zhiqiang Sun
Repairing and regenerating the unbalanced electrolytes is critical for the long-term operation of vanadium redox flow batteries (VRFBs). In this work, we propose a simple strategy to repair the unbalanced electrolytes for capacity recovery through chemical oxidation with the V(V) electrolyte and develop a method based on image analysis to obtain the electrolytes’ V(IV) ion contents. When the V(V) electrolyte with the same concentration as that of the unbalanced electrolyte is added to the unbalanced electrolyte, V(V) ions gradually oxidize V(III) ions to V(IV) ions, and the color of the electrolyte changes significantly. By extracting the RGB information of the electrolyte image, it is found that the B channel value presents the highest sensitivity to the V(IV) ion content. Thus, the relationship between them is fitted, and the R 2 of the fitted curve reaches 0.9978. Furthermore, the image analysis-based method is applied to predict the V(V) electrolyte volumes needed to repair the unbalanced electrolytes. Results show that the deviation of the B channel values between the recovered and standard V(IV) electrolytes is within 5%, demonstrating the effectiveness of the proposed repair strategy and image analysis-based method, which show great promise for practical VRFB applications.
研究领域:
能源存储
·
电化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Xingyun Hu,Xianjia Peng,Linghao Kong,Feng Zhu
The most toxic and mobile form of vanadium (V) is V(V). Thus, the oxidation of V is a subject of considerable importance since the process may increase environmental risks of V. V(IV) is known to be stable when pH < 4.5. However, in this study, stable V(IV) was oxidized almost completely in goethite suspension within 60 min at pH 2.0 and pH 4.0, correspondingly, only 25%–30% and 15%–20% of V(IV) were oxidized in equimolar Fe 3+ solution and the blank solution, respectively. The promoted oxidation of V(IV) by FeOOH is attributed to the formation of the complex, VO(OFe<) + or VO(OFe<) 2 . On the one hand, the formation of the complex caused higher pH in the interface of solid FeOOH and corresponding lower conditional potential of V(V)/V(IV) than those in bulk solutions, which facilitates the oxidation of V(IV). On the other hand, the surface group OFe < may serve as a medium that facilitating the electron transfer from V(IV) ions to dissolved oxygen molecules, also favoring the oxidation of V(IV). This study not only deepens our understanding of the transfer, transformation, and risk of V in environments, but also provides a reference to speculate the fate of similar elements in environments.
研究领域:
环境化学
·
地球化学
·
水污染控制
·
金属形态转化
·
界面过程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Junlei Zhang,Wei Zhao,Zhi Li,Gang Lu,Mingshan Zhu
Advanced oxidation processes involving the visible-light-assisted peroxymonosulfate (PMS) are emerging as promising approaches for treating antibiotic pollutants. Here, Fe(II)/V(IV) self-doped FeVO 4 nanobelts were synthesized and employed to build a visible-light-assisted PMS activation system for degrading antibiotic sulfamethoxazole (SMX). Compared with PMS/FeVO 4 , PMS/Visible light (VL), or PMS system, the PMS/FeVO 4 /VL system showed 3.9, 14.0, or 14.1 times improved for the removal of SMX, respectively. The reason behind this is the organic combination of the VL photocatalysis and transformation of Fe(II)/V(IV) to Fe(III)/V(V) over FeVO 4 , namely when photocatalytic behavior over FeVO 4 can produce electrons (e - ) and holes (h + ) to activate PMS or directly degrade SMX, the transformation of Fe(II)/V(IV) to Fe(III)/V(V) will also happen to donate some e - for PMS activation simultaneously. Such a system can also effectively remove SMX from actual water bodies such as medicine wastewater, river water, tap water, and rainwater. This work not only provides an effective system for treating SMX polluted wastewater, but also gives some new insights to understanding the mechanism involving Fe-based binary metal oxide activating peroxymonosulfate.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）