Hydrothermal Transformation of Glycerol to Lactic Acid in Alkaline Medium Using Cu Catalysts Obtained from Hydrotalcite-Like Precursors

The conversion of glycerol into lactic acid in alkaline medium using heterogeneous catalysts has been highlighted and proved to be an efficient alternative the conventional fermentative route. This work investigated production from copper obtained hydrotalcite-like precursors a continuous flow reaction system effect different loading on catalytic behaviors terms yield selectivity acid. were synthesized by coprecipitation method characterized XRF, XRD, N2 adsorption–desorption, H2-TPR, CO2-TPD, dispersion (i.e., metal atoms exposed) was determined N2O oxidation. performed for 30 h at 240 °C, 35 atm, space velocity (WHSV) 2 h−1, solution 10 vol% glycerol, NaOH/glycerol molar ratio 0.75. Although 30CuHT catalyst presented higher BET surface areas, Cu dispersion, basicity than 20CuHT catalyst, best results (96.5%) (64%) test with catalyst. result may related steps that occur liquid phase presence hydroxyl group ( $${\text{OH}}^{-}$$ Furthermore, high content favor hydrogenation intermediates (2-hydroxypropenal pyruvaldehyde), increasing formation 1,2-propanediol consequently reducing activity reduced non-reduced investigated, showed oxide also activity. However, reduction provides better results.