Probing carboxylate Gibbs transfer energies via liquid|liquid transfer at triple phase boundary electrodes: ion-transfer voltammetry versus COSMO-RS predictions.
Probing carboxylate Gibbs transfer energies via liquid|liquid transfer at triple phase boundary electrodes: ion-transfer voltammetry versus COSMO-RS predictions.
复制标题
探测羧酸盐吉布斯通过三相边界电极上的液体|液体转移传递能量：离子转移伏安法与 COSMO-RS 预测。
DOI：
10.1039/b803582b
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
F. Marken
中科院分区：
文献类型：
--
作者：
Stuart M. Macdonald;M. Opallo;A. Klamt;F. Eckert;F. Marken
了解液体|液体离子转移过程对于天然存在的物质如羧酸盐特别重要。在这项研究中，电化学驱动的单，二，三羧酸根阴离子转移的4-（3-苯丙基）吡啶|对三相界面体系在石墨电极上的水电解质界面进行了实验研究。采用四苯基卟啉-Mn（III/II）氧化还原体系（Mn（III/II）TPP）溶于水不混溶有机相（4-（3-苯丙基）吡啶）中，定量研究了羧酸盐转移过程的结构-吉布斯转移能关联以及溶液pH值的影响.对于二羧酸盐和三羧酸盐，部分质子化的阴离子总是优先转移，即使在pH值高于相应的pK（a）。COSMO-RS计算机模拟提供了一个定量的合理化，以及一个强大的工具，用于预测吉布斯自由能的转移数据更复杂的官能化羧酸根阴离子。结果表明，在有机相中的水的存在下，计算的吉布斯自由能有重大影响。
Understanding liquid|liquid ion transfer processes is important in particular for naturally occurring species such as carboxylates. In this study electrochemically driven mono-, di-, and tri-carboxylate anion transfer at the 4-(3-phenylpropyl)pyridine|aqueous electrolyte interface is investigated experimentally for a triple phase boundary system at graphite electrodes. The tetraphenylporphyrinato-Mn(III/II) redox system (Mn(III/II)TPP) dissolved in the water-immiscible organic phase (4-(3-phenylpropyl)pyridine) is employed for the quantitative study of the structure-Gibbs transfer energy correlation and the effects of the solution pH on the carboxylate transfer process. For di- and tri-carboxylates the partially protonated anions are always transferred preferentially even at a pH higher than the corresponding pK(a). COSMO-RS computer simulations are shown to provide a quantitative rationalisation as well as a powerful tool for predicting Gibbs free energy of transfer data for more complex functionalised carboxylate anions. It is shown that the presence of water in the organic phase has a major effect on the calculated Gibbs free energies.