Extraction of vanadium（IV） from sulphate acid solution was studied using organophosphorous-based extractants D2EHPA, EHEHPA and CYANEX 272 in kerosene. The different parameters affecting the extraction of vanadium...Extraction of vanadium（IV） from sulphate acid solution was studied using organophosphorous-based extractants D2EHPA, EHEHPA and CYANEX 272 in kerosene. The different parameters affecting the extraction of vanadium（IV） under equilibrium conditions were separately investigated to elucidate the stoichiometry of the extracted species. The distribution ratio of vanadium increased with increasing equilibrium pH of the aqueous phase, concentration of the extractants and temperature. D2EHPA was found to be a stronger extractant, having greater pH functionality than EHEHPA and CYANEX 272. Extraction of vanadium（IV） by these organophosphorous-based extractants involved cation exchange mechanism, and the extracted species appear to be VOR2（HR）2 in the low equilibrium pH and VOR2 in the higher equilibrium pH, where HR refers to the three acidic extractants.展开更多
The extraction behaviors of zinc from ammoniacal solutions were investigated using β-diketone （HA） and their mixtures with CYANEX923 or LIX84I. The effects of pH, total ammonia concentration, extractant concentrati...The extraction behaviors of zinc from ammoniacal solutions were investigated using β-diketone （HA） and their mixtures with CYANEX923 or LIX84I. The effects of pH, total ammonia concentration, extractant concentration, anion species and temperature on zinc extraction were examined. The synergistic mechanism was discussed with regard to the structure of extractant and the extracted zinc complexes. It is found that the increase of total ammonia concentration and pH inhibits zinc extraction for all extraction systems due to the formation of zinc ammine complexes in aqueous phase. This effect of HA with CYANEX923 is evidently smaller than that of HA with LIX84I or HA alone system. Effect of anion species on the zinc extraction by HA with CYANEX923 can be neglected, but this effect of HA alone and the mixture of HA with LIX84I decreases in the order of （NH4）2SO4 〉 NH4NO3 〉 NH4Cl.展开更多
研究了Cyanex272从盐酸介质中萃取Nd(Ⅲ)和Y(Ⅲ)的性能,考察了平衡相酸度、振荡时间和平衡相温度对萃取的影响。结果表明,分配比在一定时间内随振荡时间、平衡相温度的增加而增加。在pH 1.54、振荡时间为20 m in时,Nd(Ⅲ)的分配比最小;...研究了Cyanex272从盐酸介质中萃取Nd(Ⅲ)和Y(Ⅲ)的性能,考察了平衡相酸度、振荡时间和平衡相温度对萃取的影响。结果表明,分配比在一定时间内随振荡时间、平衡相温度的增加而增加。在pH 1.54、振荡时间为20 m in时,Nd(Ⅲ)的分配比最小;而在pH 2.62、振荡时间为25 min时,Y(Ⅲ)能很好地被萃取。Nd(Ⅲ)-Y(Ⅲ)能很好地分离。展开更多
基金Project (2009AA06Z106) supported by the High-tech Research and Development Program of ChinaProject (51174104) supported by the National Natural Science Foundation of ChinaProject (20115314110001) supported by the Doctoral Fund of Ministry of Education of China
文摘Extraction of vanadium（IV） from sulphate acid solution was studied using organophosphorous-based extractants D2EHPA, EHEHPA and CYANEX 272 in kerosene. The different parameters affecting the extraction of vanadium（IV） under equilibrium conditions were separately investigated to elucidate the stoichiometry of the extracted species. The distribution ratio of vanadium increased with increasing equilibrium pH of the aqueous phase, concentration of the extractants and temperature. D2EHPA was found to be a stronger extractant, having greater pH functionality than EHEHPA and CYANEX 272. Extraction of vanadium（IV） by these organophosphorous-based extractants involved cation exchange mechanism, and the extracted species appear to be VOR2（HR）2 in the low equilibrium pH and VOR2 in the higher equilibrium pH, where HR refers to the three acidic extractants.
基金Project (2007CB613601) supported by the National Basic Research Program of ChinaProject (CX2010B112) supported by Hunan Provincial Innovation Foundation for Postgraduate, China
文摘The extraction behaviors of zinc from ammoniacal solutions were investigated using β-diketone （HA） and their mixtures with CYANEX923 or LIX84I. The effects of pH, total ammonia concentration, extractant concentration, anion species and temperature on zinc extraction were examined. The synergistic mechanism was discussed with regard to the structure of extractant and the extracted zinc complexes. It is found that the increase of total ammonia concentration and pH inhibits zinc extraction for all extraction systems due to the formation of zinc ammine complexes in aqueous phase. This effect of HA with CYANEX923 is evidently smaller than that of HA with LIX84I or HA alone system. Effect of anion species on the zinc extraction by HA with CYANEX923 can be neglected, but this effect of HA alone and the mixture of HA with LIX84I decreases in the order of （NH4）2SO4 〉 NH4NO3 〉 NH4Cl.
