CONICET | Buscador de Institutos y Recursos Humanos

Acrylic acid and its esters are primary building blocks of all acrylate polymers and plastics. Currently, 100% of acrylic acid (AA) is produced from fossil oil, mostly via direct oxidation of propene. Lactic acid (LA) can be produced by chemical synthesis or by fermentation of different carbohydrates such as glucose (from starch), and the production of lactic acid is around 350 000 t/year. Therefore, the production of acrylic acid via dehydration of lactic acids (LA) is an attractive method for creating new bio-based compounds. The aim in this work was to study the dehydration of LA to produce AA with different solid acids. The infrared spectra of adsorbed pyridine was used to determine the concentration of Lewis and Br©ªnsted acid sites, and TPD of adsorbed NH3 was performed to determine the density and strength of solid acids. The dehydration of lactic acid was carried out over a fixed bed reactor at 583K, using solid acids with different acid properties such as Na(Zn,H)Y, NaZSM5, KL and ¥ã-Al2O3 The dehydration reaction from the lactic acid presents a competition reaction to produce oligomers of lactic acid. Lactate was not detected in the condensated product for the pathway of dehydration to produce acrylic acid. Strong Lewis and Br©ªnsted sites promote the decarbonylation reaction. Weak acidity formed oligomers. Results from the catalytic test show that NaY and KL zeolites are highly selective for the vapor-phase dehydration of lactic acid to acrylic acid, showing that weak acid sites promote formation of acrylic acid from the dehydration of lactic acid. The dehydration reaction from the lactic acid presents a competition reaction to produce oligomers of lactic acid. Lactate was not detected in the condensated product for the pathway of dehydration to produce acrylic acid. Strong Lewis and Br©ªnsted sites promote the decarbonylation reaction. Weak acidity formed oligomers. Results from the catalytic test show that NaY and KL zeolites are highly selective for the vapor-phase dehydration of lactic acid to acrylic acid, showing that weak acid sites promote formation of acrylic acid from the dehydration of lactic acid. The dehydration reaction from the lactic acid presents a competition reaction to produce oligomers of lactic acid. Lactate was not detected in the condensated product for the pathway of dehydration to produce acrylic acid. Strong Lewis and Br©ªnsted sites promote the decarbonylation reaction. Weak acidity formed oligomers. Results from the catalytic test show that NaY and KL zeolites are highly selective for the vapor-phase dehydration of lactic acid to acrylic acid, showing that weak acid sites promote formation of acrylic acid from the dehydration of lactic acid.