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Hydrometallurgical recycling of NdF eB magnets： Complete leaching, iron removal and electrolysis

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Journal of Rare Earths 2017年第6期35卷 574-584页

作者： Mehmet Ali Recai Onal chenna rao borra Muxing Guo Bart Blanpain Tom Van Gerven Department of Materials Engineering University of Leuven Kasteelpark Arenberg 44 3001 Leuven Belgium Process Engineering for Sustainable Sys-terns (ProcESS) Department of Chemical Engineering University of Leuven Celestijnenlaan 200F 3001 Leuven Belgium

NdFeB magnets currently dominate the magnet market. Supply risks of certain rare earth metals（REM）, e.g. Nd and Dy, impose efficient recycling schemes that are applicable to different types and compositions of these magnets with minimum use of chemicals and waste generation. In this study, a hydrometallurgical method was studied that could be adjusted to recover not only REM, but also other valuable metals（e.g.Co, Ni and Cu） that co-existed in the magnet. The magnet powders were completely dissolved in a dilute sulfuric acid solution giving more than 98% of dissolved iron in the ferrous state. Chemical oxidation of Fe-（2＋） into Fe-（3＋） by the addition of MnO 2 required only 1 h at ambient temperature. It was then possible to precipitate more than 99% of this ferric iron by adjusting the pH of the solution above 3 with either Ca（OH）2 or MnO additions. However, the addition of Ca（OH）2 resulted in the formation of gypsum and up to ca. 23% REM losses, possibly via co-precipitation into the gypsum. MnO elevated the Mn-（2＋） concentration in the solution. However, it was found to be problematic that subsequent direct electrolysis removed Mn and Co. Low anodic current efficiencies（ACE） resulted in high energy consumption（EC）, while incomplete Mn and Co removals and undesired REM losses were reported. Pre-electrolysis removals of REM and/or Co by oxalate and/or sulfide precipitation were proven to be successful and selective, but this enlarged the flowsheet considerably with only minor improvement of the Mn removal, ACE and EC.

关键词： electrolysis magnet recycling precipitate leaching anodic subsequent ferrous dissolved leachate

Improvement of Plasma Performance with Lithium Wall Conditioning in Aditya Tokamak

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Plasma Science and Technology 2013年第2期15卷 123-128页

作者： M. B. CHOWDHURI R. MANCHANDA J. GHOSH S. B. BHATT Ajai KUMAR B. K. DAS K. A. JADEJA P. A. RAIJADA Manoj KUMAR S. BANERJEE Nilam RAMAIYA Aniruddh MALI Ketan M. PATEL Vinay KUMAR P. VASU R. BHATTACHARYAY R. L. TANNA Y. Shankara JOISA P. K. ATREY C. V. S. rao D. chenna REDDY P. K. CHATTOPADHYAY R. JHA Y. C. SAXENA Aditya team Institute for Plasma Research Bhat Gandhinagar 382 428 India

Lithiumization of the vacuum vessel wall of the Aditya tokamak using a lithium rod exposed to glow discharge cleaning plasma has been done to understand its effect on plasma performance. After the Li-coating, an increment of ~100 eV in plasma electron temperature has been observed in most of the discharges compared to discharges without Li coating, and the shot reproducibility is considerably improved. Detailed studies of impurity behaviour and hydrogen recycling are made in the Li coated discharges by observing spectral lines of hydrogen, carbon, and oxygen in the visible region using optical fiber, an interference filter, and PMT based systems. A large reduction in O I signal （up to ~40% to 50%） and a 20% to 30% decrease of Ha signal indicate significant reduction of wall recycling. Furthermore, VUV emissions from O V and Fe XV monitored by a grazing incidence monochromator also show the reduction. Lower Fe XV emission indicates the declined impurity penetration to the core plasma in the Li coated discharges. Significant increase of the particle and energy confinement times and the reduction of Zeff of the plasma certainly indicate the improved plasma parameters in the Aditya tokamak after lithium wall conditioning.

关键词： lithiumization wall conditioning impurity Aditya tokamak

转录因子和转录激活因子4人细胞毒性T淋巴细胞相关抗原-4和染色体9p21．3遗传多态性与闽南地区人群类风湿关节炎相关性研究

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中华风湿病学杂志 2016年第6期20卷 372-377页

作者：郑晨娜饶华春罗彩林王清瑶杨会勇刁勇泉州医学高等专科学校基础医学部 362000 福建省泉州市正骨医院临床检验科华侨大学生物医学学院分子药物研究院

目的探讨转录因子和转录激活因子4（STAT4）rs7574865、人细胞毒性T淋巴细胞相关抗原-4（CTLA-4）rs3087243基因以及染色体9p21.3 rs1333049单核苷酸多态性（SNPs）与闽南地区人群RA的关联。方法选取119例RA患者和125名健康对照者，应... 详细信息

目的探讨转录因子和转录激活因子4（STAT4）rs7574865、人细胞毒性T淋巴细胞相关抗原-4（CTLA-4）rs3087243基因以及染色体9p21.3 rs1333049单核苷酸多态性（SNPs）与闽南地区人群RA的关联。方法选取119例RA患者和125名健康对照者，应用三引物扩增法（AS-PCR）对RA相关的3个SNPs位点进行基因分型，并应用SPSS 18.0统计软件分析不同基因型与RA发病的相关性。采用χ2检验和Logistic回归模型进行分析。结果RA组STAT4 rs7574865各基因型分布频率与健康对照组比较，差异有统计学意义（P〈0.01），与G/T杂合基因型相比，TT与GG纯合性携带者患病风险要低（OR=0.498和0.300，P=0.018和P=0.002）；CTLA-4 rs3087243各基因型分布频率与健康对照组比较，差异无统计学意义（χ^2=4.083，P=0.130），但根据计算，其中与A/G基因型相比，GG型携带者患病风险要低（OR=0.580，P=0.04）；9p21.3上的SNP（rs1333049）无论基因型还是等位基因在RA与健康志愿者组间差异无统计学意义，但是经计算发现与GG基因型携带者相比，CC和GC携带者发病风险要低（OR=0.565，P=0.049 5）。结论STAT4 rs7574865和CTLA-4 rs3087243和rs1333049与闽南地区人群RA发病均有一定相关性。

关键词：关节炎类风湿多态性单核苷酸转录因子和转录激活因子4 人细胞毒性T淋巴细胞相关抗原-4 染色体9p21.3