ON LINE CHROMATOGRAPHIC ANALYSIS OF THE PRODUCTS RESULTING FROM THE ELECTROCATALYTIC OXIDATION OF D-GLUCOSE ON PT, AU AND ADATOMS MODIFIED PT ELECTRODES .1. ACID AND NEUTRAL MEDIA

Using suitable potential programmes, sustained electrolysis of aqueous solution Of D-glucose, in perchloric and phosphate buffered media were carried out on Pt, Au and adatoms (Pb, Tl, Bi) modified Pt electrodes. The reaction products in solution as well in the gas phase were analysed by HPLC and GC chromatographic techniques, and their concentration was followed vs. the time of electrolysis. It is confirmed that whatever the experimental conditions, gluconic acid is the main reaction product. However, many other carboxylic acids (among which glucaric, glucuronic, tartaric, glyoxylic, oxalic, glycolic and formic acids) were detected. Their concentration distribution was found to depend mainly on the catalytic properties of the surface. For example, with Bi adatom modified Pt, a significant amount of glucuronic acid could be produced.