Simple and Effective HPLC Method for Elucidating Glycerol Oxidation Products

The glycerol electrooxidation reaction (GEOR) has been gaining increasing attention as a substitute for the oxygen evolution reaction to improve H₂ production while producing high-value-added products. During GEOR, several C₃, C₂, and C₁ species can be generated, making the detection and quantification of all these products a complex challenge that has not been fully addressed yet. Our study describes the development and optimization of a simple high-performance liquid chromatography (HPLC) method, capable not only of detecting but also simultaneously quantifying eight different GEOR products using a single diode array detector (DAD). To address possible overlapping signals, an indirect quantification approach is also proposed. The optimized method has been applied to real electrochemical GEOR systems, employing a Ni foil in alkaline media or a Pt foil in acidic media as oxidation electrocatalysts. Results show how product distributions varied significantly along with the pH, with formate being the main product in alkaline conditions (∼68% selectivity), whereas glyceraldehyde and dihydroxyacetone were the major products in acidic conditions (∼40% and ∼26%, respectively).