Electrochemically synthesis of the pirazine-2,3-dicarboxylic acid. Cyclic voltammetry studies on cooper electrode [articol]

Abstract

The previous studies shows that the KMnO₄ regeneration used in chemical oxidation of chinoxaline to form the pyrazine-2,3-dicarboxylic acid is possible on platinum in chinoxaline absence[1] or his presence[2] and on nickel electrode[3]. The purpose of this paper is investigation of the KMnO₄ regeneration process on copper electrode. The studies was made by cyclic voltammetry at a concentrations of support electrolyte (KOH ) of about 5 to 10%, at 25-40°C temperature, KMnO₄ concentration until 6•10⁻² M and maximum concentration of quinoxaline until 2.61•10⁻² M in electrolite solution. On copper electrode it’s possible the process of oxidation of Mn⁶⁺ to Mn⁷⁺. Anodic regeneration of Mn⁷⁺ is favoured by rise of : KOH concentration, temperature, Mn⁷⁺ and Mn⁶⁺ concentration, quinoxaline.