Extraction of Nb(v) by quaternary ammonium-based solvents: toward organic hexaniobate systems.
Extraction of Nb(v) by quaternary ammonium-based solvents: toward organic hexaniobate systems.
复制标题
用季铵基溶剂萃取 Nb(v)：走向有机己铌酸盐系统。
作者：
G. Deblonde;A. Chagnes;Marie;Valérie Weigel;G. Cote
研究了使用季铵溶液，特别是在脂肪族稀释剂中稀释的Aliquat® 336从碱性水性介质中溶剂萃取Nb（V）。的hexaniobate离子（HxNb 6 O 19 x-8）被提取到有机相，在室温下，在几分钟内，非常高的产量，提供容易获得的hexaniobates的有机溶液。发现几个参数影响HxNb 6 O 19 x-8的提取，包括碱金属阳离子的性质和浓度，证实了先前描述的多氧铌酸盐的微妙效果，如与碱金属离子的离子配对。如果水相中存在竞争性阴离子，则Aliquat® 336对HxNb 6 O 19 x-8的萃取也会受到影响HxNb_6 O_（19 x-8）对Na ~+的共萃取以及对水分子的共萃取，表明萃取剂的自缔合。所提出的液-液萃取通用系统为创新的铌（和潜在的钽）湿法冶金工艺铺平了道路，它也可以提供更直接的路线，探索在有机溶剂中的hexaniobates的化学。
Solvent extraction of Nb(v) from alkaline aqueous media using quaternary ammonium solutions, especially Aliquat® 336 diluted in an aliphatic diluent, was investigated. The hexaniobate ions (HxNb6O19x-8) were extracted into the organic phase with very high yields at room temperature and within a few minutes, affording easy access to organic solutions of hexaniobates. Several parameters were found to influence the extraction of HxNb6O19x-8 including the nature and concentration of alkali cations, confirming subtle effects previously described for polyoxoniobates such as ion-pairing with alkali ions. The extraction of HxNb6O19x-8 with Aliquat® 336 is also influenced if competing anions are present in the aqueous phase (NO3-, Cl-, C2O42-, SO42- and CO32-) and varies with the pH mainly due to the competitive extraction of hydroxide ions at high pH. The co-extraction of sodium ions with HxNb6O19x-8 was observed as well as the co-extraction of water molecules, suggesting a self-association of the extractant. The proposed liquid-liquid extraction generic system paves the way for innovative niobium (and potentially tantalum) hydrometallurgical processes and it may also afford more direct routes for exploring the chemistry of hexaniobates in organic solvents.
影响因子：
4.6
作者：
G. Deblonde;Cristina Coelho-Diogo;A. Chagnes;G. Cote;Mark E. Smith;J. Hanna;D. Iuga;C. Bonhomme
通讯作者：
G. Deblonde;Cristina Coelho-Diogo;A. Chagnes;G. Cote;Mark E. Smith;J. Hanna;D. Iuga;C. Bonhomme