Nd（EDTA）与酸性媒介黄2G的混配络合反应动力学和反应机理

Kinetics and mechanism of the reaction of Nd(EDTA) with solochrome yellow 2G

研究了ＮｄＹ（Ｙ＝ＥＤＴＡ）与酸性媒介黄２Ｇ［２－羟基－５－（４－苯磺基）偶氮基苯甲酸的钠盐，ＮａＨ２Ｌ·２Ｈ２Ｏ］在ｐＨ７．２～９．２及离子强度０．２５ｍｏｌ／ｋｇ（ＮａＮＯ３）时混配络合物的生成反应动力学．实验求得ＮｄＹ与ＨＬ及Ｌ的反应速率常数（ｋ１，ｋ－１及ｋ２，ｋ－２）．混配给合物生成常数的计算值ＫＮｄＹＬ（等于ｋ２／ｋ－２）与分光光度法求得的数值基本一致．还研究了混配给合物ＮｄＹＬ的酸水解动力学行为．

The kinetics of the mixed - ligand complx formation reaction of Nd(EDTA) with solochrome Yellow 2G [ sodium salt of 2 hydroxy - 5 - (4 - sulphophenyl) azo benzoic acid, NaH2L·2H2O] have been investigated in the PH range 7.2 ～ 9.2 at ionic strength 0.25 mol·kg-1(NaNO3). The reaction rate constants of NdY with HL (k1, k-1)and with L(k2, k-2) have been obtained experimentally. The calculated mixed - ligand complex formation constant KNdYL(i .e. k2/k-2)is close to the spectrophotometric result.The kinetics behavior of acid hydrolysis of Nd(EDTA)L has also been studied.