Revealing Reaction Conditions to Drive the Oxidation Reaction of Hydroxyacetone to Lactic Acid on Cu/ZrO₂ Catalyst

Lactic acid (LA) is an essential chemical that produces high-value-added products across various industries. However, its traditional production via sugar fermentation raises environmental concerns, highlighting the need for alternative, biomass-based production methods. This study investigates the production of LA from hydroxyacetone (HA) oxidation using a Cu/ZrO₂ catalyst prepared by the incipient impregnation method. The catalyst was characterized through several techniques such as ICP-MS, SEM-EDS, N₂-physisorption, XRD, XPS, H₂-TPR, N₂O chemisorption, NH₃-TPD, CO₂-TPD, Pyridine FT-IR, and TPO analyses, revealing well-dispersed copper species in the zirconia’s tetragonal phase, imparting distinctive redox and acid-base properties. In this contribution, we progressively assessed some reaction parameters and established conditions, including a temperature of 120 °C, a specific HA concentration, and an HA-to-catalyst ratio, to boost the lactic acid performance. Moreover, computational chemistry calculations of Gibbs free energy on model intramolecular and intermolecular Cannizzaro-type reactions demonstrated a distinct preference for lactic acid formation over pyruvic acid, offering valuable insights into the reaction mechanism and spontaneity.