利用恒界面池研究了二壬基萘磺酸(DNNSA)反胶团溶液萃取废水中锌离子的动力学.考察了搅拌转速、两相接触界面积、DNNSA和初始锌离子浓度以及温度对萃取速率的影响,得到了DNNSA反胶团萃取废水中锌离子的动力学方程并对萃取机理进行了探讨...利用恒界面池研究了二壬基萘磺酸(DNNSA)反胶团溶液萃取废水中锌离子的动力学.考察了搅拌转速、两相接触界面积、DNNSA和初始锌离子浓度以及温度对萃取速率的影响,得到了DNNSA反胶团萃取废水中锌离子的动力学方程并对萃取机理进行了探讨.实验结果表明:水相内化学反应为萃取过程的速率控制步骤.当搅拌速率在200 r·min-1时出现与搅拌强度无关的化学反应动力学"坪区",在动力学"坪区",锌离子萃取速率与萃取剂DNNSA浓度和水相锌离子浓度成正比,温度升高萃取速率增加,萃取反应活化能为61.69 k J·mol-1.展开更多
文章采用恒界面法对乳化液膜分离Cr(Ⅲ)的液膜内相反萃步骤进行了研究,考察了搅拌速度、温度、界面面积、水相p H值、DEHPA[二(2-乙基己基)磷酸]浓度和络合物浓度对反萃速率的影响,得到反萃反应的动力学与热力学数据,并推导出反萃的反...文章采用恒界面法对乳化液膜分离Cr(Ⅲ)的液膜内相反萃步骤进行了研究,考察了搅拌速度、温度、界面面积、水相p H值、DEHPA[二(2-乙基己基)磷酸]浓度和络合物浓度对反萃速率的影响,得到反萃反应的动力学与热力学数据,并推导出反萃的反应机理。实验结果表明:搅拌速度大于0.45 m/s时出现与搅拌强度无关的化学反应控制"坪区",且反萃速率与界面面积成正比,此时反应属于扩散和化学反应共同控制,并且反应主要发生在相界面上;由温度与反萃速率的关系得知,该反萃反应是一个放热反应,反应的活化能Ea=24.25 k J/mol,焓变ΔH=-55.85 k J/mol,熵变ΔS=-566.37 J/mol,在T=308 K时ΔG=118.59 k J/mol;在控制步骤反应式中,DEHPA反应级数为0,络合物浓度和水相氢离子的反应级数为1,并推导出反萃反应的控制步骤的方程式为r=k0[Cr(OH)2HL2(o)][H+(w)]。展开更多
The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a const...The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a constant interfacial area cell with laminar flow were studied,just to elucidate the extraction mechanism and the mass transfer models.The data were analyzed in terms of pseudo-first-order constants.The effects of stirring speed,specific interfacial area and temperature on the extraction rate in both systems were discussed,suggesting that the extractions were mixed bulk phases-interfacial control process.Supported by the experimental data,the corresponding rate equations for Ce(Ⅳ) extraction system and Ce(Ⅳ)-F^- mixture extraction system were obtained.The experimental results indicated the rate-controlling step.The kinetics model was deduced from the rate-controlling step and consistent with the rate equation.展开更多
文摘利用恒界面池研究了二壬基萘磺酸(DNNSA)反胶团溶液萃取废水中锌离子的动力学.考察了搅拌转速、两相接触界面积、DNNSA和初始锌离子浓度以及温度对萃取速率的影响,得到了DNNSA反胶团萃取废水中锌离子的动力学方程并对萃取机理进行了探讨.实验结果表明:水相内化学反应为萃取过程的速率控制步骤.当搅拌速率在200 r·min-1时出现与搅拌强度无关的化学反应动力学"坪区",在动力学"坪区",锌离子萃取速率与萃取剂DNNSA浓度和水相锌离子浓度成正比,温度升高萃取速率增加,萃取反应活化能为61.69 k J·mol-1.
文摘文章采用恒界面法对乳化液膜分离Cr(Ⅲ)的液膜内相反萃步骤进行了研究,考察了搅拌速度、温度、界面面积、水相p H值、DEHPA[二(2-乙基己基)磷酸]浓度和络合物浓度对反萃速率的影响,得到反萃反应的动力学与热力学数据,并推导出反萃的反应机理。实验结果表明:搅拌速度大于0.45 m/s时出现与搅拌强度无关的化学反应控制"坪区",且反萃速率与界面面积成正比,此时反应属于扩散和化学反应共同控制,并且反应主要发生在相界面上;由温度与反萃速率的关系得知,该反萃反应是一个放热反应,反应的活化能Ea=24.25 k J/mol,焓变ΔH=-55.85 k J/mol,熵变ΔS=-566.37 J/mol,在T=308 K时ΔG=118.59 k J/mol;在控制步骤反应式中,DEHPA反应级数为0,络合物浓度和水相氢离子的反应级数为1,并推导出反萃反应的控制步骤的方程式为r=k0[Cr(OH)2HL2(o)][H+(w)]。
基金Project (2012CBA01202) supported by the National Basic Research Program of ChinaProject (51174184) supported by the National Natural Science Foundation of China+2 种基金Project (KGZD-EW-201-1) supported by the Key Research Program of the Chinese Academy of SciencesProject (BK2013030) supported by Science and Technology Plan of Nantong City,ChinaProject (RERU2014016) supported by Open Subject of Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,China
文摘The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a constant interfacial area cell with laminar flow were studied,just to elucidate the extraction mechanism and the mass transfer models.The data were analyzed in terms of pseudo-first-order constants.The effects of stirring speed,specific interfacial area and temperature on the extraction rate in both systems were discussed,suggesting that the extractions were mixed bulk phases-interfacial control process.Supported by the experimental data,the corresponding rate equations for Ce(Ⅳ) extraction system and Ce(Ⅳ)-F^- mixture extraction system were obtained.The experimental results indicated the rate-controlling step.The kinetics model was deduced from the rate-controlling step and consistent with the rate equation.