Ethylene glycol electrochemical oxidation at platinum probed by ion chromatography and infrared spectroscopy

Wet chemical methods were used in combination with in situ infrared spectro scopy to identify and quantify soluble products formed during ethylene glyc ol electrochemical oxidation on platinum. A small volume electrolysis techn ique allowed reactions to be performed in samples of 150 mu l in contact wi th a small, bead-type single crystal electrode. Following reaction, 50-100 mu l aliquots were assayed for aldehydes and carboxylic acids. Glycolaldehy de (HOCH2CHO), and glycolic (HOCH2COOH) and oxalic ((HOOC)(2)) acids were d etected following the 360 s electrolysis of 0.2 M ethylene glycol in 0.1 M HClO4 at potentials in the range 0.0-0.6 V (vs. SCE). Determination of the carboxylic acids by ion chromatography aided the assignment of carboxylate vibrational bands in in situ infrared spectra. (C) 1998 Elsevier Science Lt d. All rights reserved.