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采用线性扫描极谱法、循环伏安法及恒电位电解法在NH4Cl-NH3.H2O(pH9.5)缓冲液中研究了酮洛芬(KPF)的伏安行为和极谱催化波的产生机理。结果表明,KPF的羰基首先发生1e-和1H+还原,产生中间体质子化羰基自由基,该自由基再以同样方式进一步还原生成相应的羟基化合物,并伴随有化学反应;引入K2S2O8后,S2O82-作为配位体与吸附在电极表面质子化的KPF形成缔合物,引起峰电位负移,S2O82-及其还原中间产物SO4.-氧化经1e-和1H+还原的KPF羰基自由基,使峰电流显著增加,从而产生了KPF的吸附缔合平行极谱催化波。测得S2O82-氧化KPF质子化羰基自由基的表观速率常数Kf=1.2×104/s。
The voltammetric behavior of ketoprofen (KPF) and the mechanism of polarographic catalytic wave were studied by linear sweep polarography, cyclic voltammetry and potentiostatic electrolysis in NH4Cl-NH3.H2O (pH9.5) buffer . The results showed that the carbonyl group of KPF was first reduced by 1e- and 1H + to produce the intermediate protonated carbonyl free radical which was further reduced in the same manner to form the corresponding hydroxyl compound with the chemical reaction. After the introduction of K2S2O8, S2O82- As ligand and KPF adsorbed on the protonated surface of the electrode to form an associate, causing a negative shift in peak potential, S2O82- and its reduced intermediate SO4- oxidize the KpF carbonyl radicals reduced by 1e- and 1H +, causing the peak current Significantly increased, resulting in KPF adsorption association dipolar catalytic wave. The apparent rate constant Kf of protonated carbonyl radical of S2O82-oxidized KPF was measured to be 1.2 × 10 4 / s.