Kinetics of the Oxidation of Ethylenediaminetetraacetato and<i>N</i>-(2-Hydroxyethyl)ethylenediamine-<i>N</i>,<i>N</i>′,<i>N</i>′-triacetato Complexes of Cobalt(II) by Hydrogen Peroxide in Aqueous Acidic Medium
作者:Pradyot Banerjee、Mahesh P. Pujari
DOI:10.1246/bcsj.54.2496
日期:1981.8
Kinetics of the oxidation of Co(II) complexes, Co(edta)2− and Co(hedta)− [H4edta=ethylenediaminetetra-acetic acid and H3hedta=N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid] have been studied in aqueous acidic medium (pH 3.6–4.8) at 30–60 °C. The reactions were shown to exhibit second-order kinetics, first-order in each of the reactants. In the pH range studied, the rates of reaction showed
Co(II) 配合物 Co(edta)2− 和 Co(hedta)− [H4edta=乙二胺四乙酸和 H3hedta=N-(2-羟乙基)乙二胺-N,N',N'-的氧化动力学[三乙酸]已在 30–60 °C 的水性酸性介质 (pH 3.6–4.8) 中进行了研究。这些反应显示出二级动力学,在每个反应物中都是一级动力学。在研究的 pH 范围内,反应速率显示出反向 [H+] 依赖性,这可以根据酸碱平衡 H2O2\oversetKa\ightleftharpoonsHO2−+H+ 来解释。应用极限条件 [H+]>>Ka, [H2O2]>>[HO2−],速率定律由 d[CoIII−L]⁄dt=2kH2O2+kHO2−Ka[H+]−1} 给出[CoII-L] [H2O2] 其中 L 表示两种情况下配体的一般形式。在 30 °C (I, 0.5 mol dm-3) 下,获得的值为 kH2O2=(5.6±0