Oxidation of dicarboxylic acid viz-oxalic acid by pyridiniumdichromate (PDC) in perchloric acid medium has been studied. Active oxidizing species involved is protonated PDC. First order plot is observed for log(a-x) versus time. Effect of concentration of PDC, HClO4, Mn(II), Ce(III) and ionic strength has been investigated. Thermodynamic parameters have been evaluated. Energy of activation is 51.22 kJ mol-1. Entropy of activation is low and negative. The activation energy does not correspond to C-C bond breaking, but the reaction products indicate C-C bond breaking. A cyclic complex formation, which undergoes C-C fission, has been suggested.
Oxalic acid, Pyridiniumdichromate, Oxidation, Kinetics