摘要
研究P507-Cyanex272钠皂协同萃取剂在同一水相中同时萃取Co2+,Ni2+的动力学机制,用以研究动力学层面上Co2+,Ni2+分离的可能和效果。文中测得P507-Cyanex272钠皂协同萃取Co2+,Ni2+的表观活化能分别为23.76和16.63 kJ·mol-1。综合搅拌速度和温度对萃取速率的影响,判定该协萃体系下Co2+的控制机制为扩散-化学反应混合控制,Ni2+的控制机制为扩散控制。Co2+和Ni2+的萃取速率都与层流恒界面池的恒界面积大小成正比,结合有机磷酸钠皂萃取金属离子的反应机制,认为该萃取反应区是两相界面层,或是靠近有机相一侧的双电子层区。用起始速率法测定了水相金属离子浓度和有机相萃取剂浓度分别对Co2+,Ni2+萃取速率的影响。测出Co2+浓度、Ni2+浓度、P507钠皂浓度、Cyanex272钠皂浓度4个影响因素对应Co2+,Ni2+的反应级数分别为0.98,0.48,(0.65,0.89),(0.42,0.39),确定了P507-Cyanex272钠皂协萃体系对Co2+的协萃反应速率方程式为:r=k[NaA1]0.65(o)[NaA2]0.42(o)[Co2+]0.98(i).
The kinetics mechanism of PS07-Cyanex272 saponated synergistic solvent extractant in Co^2＋ and Ni^2＋ co-extraction in aqueous solution, the possibility and the effectivity of the separation for cobalt and nickel were studied. The results showed that the sur- face activation energy of cobalt and nickel in the reaction was 23.76 and 16.63 kJ.mol^-1 respectively. After considering the influence of the velocity of stir and temperature on the extraction, it was determined that the extraction mechanism of cobalt under the above syn- ergistic solvent extraction system was diffusion and chemical reaction controlled process, while the extraction mechanism of nickel was diffusion controlled process. The extraction rate of cobalt and nickel was in proportion to the constant interfacial area of the Laminar flow constant interface pool device, considering reaction mechanism of organophosphorus acid in the extraction of metal ions, it was thought that the reaction area happened on the interface of the two phases or the double electronic shell near the organic phase side. The use of initial rate method to determine the influence of the aqueous metal concentration and organic extractant concentration with the cobalt and nickel extraction rate was surveyed. As a result, the reaction order for cobalt and nickel of the four influential factor in- cluding cobalt concentration, nickel concentration, 1＇507 saponated extractant concentration and Cyanex272 saponated extractant con- centration, was 0.98, 0.48, （0.65, 0.89）, （0.42, 0.39） respectively. The extractive reaction rate equation for cobalt in the PS07- Cyanex272 saponated synergistic solvent extraction system was： r =k[NaA1]^0.65（o）[NaA2]^0.42（o）[Co^2＋]^0.98（i）
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2013年第6期939-945,共7页
Chinese Journal of Rare Metals
基金
国家科技部重点基础研究发展计划(973计划)(2010CB630906)
国家科技部高技术研究发展计划(863计划)(2012AA060502)资助项目
