盐对水溶液中1,2,3 - 丙三羧酸酯的质子化以及碱金属和碱土金属配合物形成的影响。

Salt effects on the protonation and on alkali and alkaline earth metal complex formation of 1,2,3-propanetricarboxylate in aqueous solution.

作者信息

De Stefano C, Foti C, Gianguzza A

机构信息

Dpt. Chimica Inorganica, Analitica e Struttura Molecolare dell' Università, Salita Sperone 31, S. Agata di Messina, I-98166 Messina, Italy.

出版信息

Talanta. 1994 Oct;41(10):1715-22. doi: 10.1016/0039-9140(94)e0110-d.

DOI:10.1016/0039-9140(94)e0110-d

PMID:18966125

Abstract

The protonation of 1,2,3-propanetricarboxylate (tricarballylate, tca) was studied in LiCl, NaCl, KCl, MgCl(2), CaCl(2) and tetraethylammonium iodide (Et(4)NI) aqueous solutions, at 25 degrees C, in the ionic strength range 0 < I < 1M, using the pH-metric technique. The differences between protonation constants determined in Et(4)NI and those determined in the other background salts were interpreted in terms of complex formations. Least squares calculations are consistent with the formation of MLH(j) (j = 0,1.2), M(2)LH(i) (i = 0,1,2), M(2)L species, when M = Mg(2+), Ca(2+). Potentiometric measurements performed in mixed NaClKCl, NaClCaCl(2) and MgCl(2)CaCl(2) solutions showed the formation of mixed metal complexes NaKL, NaKHL, NaCaL and CaMgL. The dependence on ionic strength of protonation and complex formation constants was evaluated using a simple Debye-Hückel type equation.

摘要

在25℃下，于离子强度范围0 < I < 1M的LiCl、NaCl、KCl、MgCl₂、CaCl₂和碘化四乙铵（Et₄NI）水溶液中，采用pH测量技术研究了1,2,3 - 丙三羧酸根（柠檬酸根，tca）的质子化。根据络合物的形成来解释在Et₄NI中测定的质子化常数与在其他背景盐中测定的质子化常数之间的差异。当M = Mg²⁺、Ca²⁺时，最小二乘法计算结果与MLHⱼ（j = 0,1,2）、M₂LHᵢ（i = 0,1,2）、M₂L物种的形成一致。在混合的NaCl - KCl、NaCl - CaCl₂和MgCl₂ - CaCl₂溶液中进行的电位测量表明形成了混合金属络合物NaKL、NaKHL、NaCaL和CaMgL。使用一个简单的德拜 - 休克尔型方程评估了质子化和络合物形成常数对离子强度的依赖性。