Relative Basicity of Trioctylamine to Carboxylic Acid in Selected Organic Diluents  

作　　者：单欣昌 秦炜 戴猷元 

机构地区：[1]State Key Laboratory of Chemical Engineering,Department of Chemical Engineering,Tsinghua University,Beijing 100084,China

出　　处：《Chinese Journal of Chemical Engineering》2005年第6期747-750,共4页中国化学工程学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China (No. 29836130).

摘　　要：The relative basicity of trioctylamine （TOA）, pKa,BS, in protic polar diluent （1-octanol）, non-protic polar diluent [methyl iso-butyl ketone （MIBK）] and inert diluent （CCl4） were determined for 11 mono-carboxylic acids, and the dependence of PKa,BS on the nature of solute and diluent type was discussed. The results show that pKa,BS determined by half neutralization with the solute carboxylic acid is in the order of 1-octanol〉MIBK〉CCl4 for a fixed TOA concentration, and it increases with increasing acidity and hydrophobicity of the carboxylic acid. Compared with two parameters of the solute extracted （acidity and hydrophobicity）, pKa,BS is more sensitive to hydrophobicity of the acid. A mathematic equation representing relationship between the apparent extraction equilibrium （K11） and the system properties （PKa,BS and pKa） was proposed： 1g K11 = 2pKa,BS=pKa. It is proved that the extraction equilibrium of mono-carboxylic acids can be predicted by the above equation with reasonable accuracy.trioctylamine ( TOA )的相对盐基度，pK_(一，噻开黑)在 protic polar diluent ( 1-octanol )， non-protic polar diluent [甲基.异丁基酮( MIBK )]并且惰性diluent ( CCl_4 )为pK_的 11 单音羧基的酸，和依赖被决定(一，噻开黑)在溶质和diluent 的性质上，类型被讨论。结果显示出那pK_(一，噻开黑)与溶质由半中立化决定羧酸在为 fixedTOA 集中的 l-octanol>MIBK>CCl_4 的顺序，并且它与与提取的溶质(酸味和 hydrophobicity )的二个参数增加 carboxylicacid.Compared 的酸味和 hydrophobicity 增加，pK_(一，噻开黑)对 acid.A 的 hydrophobicity 更敏感代表在明显的抽取平衡(K_( 11 ))和系统性质之间的关系的数学方程(pK_(一，噻开黑)并且 pK_a )被建议：Ig K_(11 )=2pK_( 一，噻开黑)- pK_a.It 被证明抽取平衡 ofmono 羧基的酸能被上述方程与合理精确性预言。

关 键 词：relative basicity trioctylamine （TOA） mono-carboxylic acid extraction equilibrium 

分 类 号：O621.25[理学—有机化学]