水溶液中四氮杂四乙酸大环与金属离子络合物的稳定性

Stability of Metals-Cyclic. Tetraazatetraacetic Acids Complexes in Aqueous Solution

本文采用pH电位滴定技术和计算机拟合,获得在20,25,30和40℃,0.5mol/LKCI水溶液中H_4L(5,12-二苯基-7,14-二甲基-1,4,8,11-四氮杂环+四烷-N′,N″,N′″,N″″-四乙酸)的分步加质子常数及反应热焓值.又在40℃条件下测定了H_4L与Cu^(2+),Ni^(2+),Co^(2+),Zn^(2+),Mn^(2+),Cd^(2+),Mg^(2+),Ca^(2+),Sr^(2+),Ba^(2+),络合物的稳定常数,并对结果进行了讨论.

The protonation constants of the macrocycle H4L(5,12-diphenyl-7, 14-dimethyl-1,4,8,11-tetraazamacrocyclotetradecane-N' ,N',N'',N ''-tetraacetic acid)in 0. 5 mol/L KCl at 20,25,30 and 40℃ were determined by potentiometric titration and computer fitting. The enthalpies of protonation reaction in the solution were given. The stability constants of H4L with Cu2+, Ni2+, Co2+, Zn2+, Mn2+, Cd2+Mg2+, Ca2+, Sr2+, Ba2+ were determined by the same method at 40℃. The results obtained were discussed.