RT info:eu-repo/semantics/article
T1 Optimization of second‐generation lactic acid from corn stover by alkaline catalysis in subcritical water reaction medium
A1 Candela Gil, Helena
A1 Illera Gigante, Alba Ester
A1 Barea Gómez, Pedro
A1 Ruiz Pérez, María Olga
A1 Beltrán Calvo, Sagrario
A1 Sanz Díez, Mª Teresa
K1 Alkaline catalysis
K1 Subcritical water
K1 Lactic acid
K1 Corn stover
K1 Molar ratio OH-/sugar monomers
K1 Ingeniería Química
K1 Chemical engineering
K1 Biotecnología alimentaria
K1 Food-Biotechnology
K1 Bioquímica
K1 Biochemistry
AB The optimization of hydrothermal lactic acid (LA) production from corn stover using Ca(OH)2 as catalyst was investigated. Initial studies with a 9 g L−1 glucose solution, and different Ca(OH)2 concentrations, in the range of 0.025–0.1 M, identified 0.075 M as the optimal concentration. Ca(OH)2 acted both as catalyst and reactant, neutralizing LA, and other organic acids produced, primarily acetic and formic acids. Excess Ca(OH)2 was required to maintain the alkaline environment necessary for LA production, achieving 3.5 g LA L−1 with a 40% yield. Lactic acid production from corn stover was studied at temperatures ranging from 90 to 260 °C with 0.075 M Ca(OH)2 and a biomass loading of 5 wt%. Higher temperatures increased LA production reaching 5.9 g LA L−1 with 15.1% of yield at 260 °C. The lower value of the yield compared with that obtained from glucose was attributed to the lower OH−/sugar monomer molar ratio, which was 3 for glucose, but only 0.65 for corn stover. To counteract organic acid formation, Ca(OH)2 concentrations up to 1.5 M were tested. The OH−/sugar monomer molar ratio emerged as a key design parameter, with an optimum value of 2.61, resulting in 12.4 g LA L−1 and 32% yield. This ratio compensates Ca(OH)2 consumption in neutralization reactions and minimizes excess base, which primarily remained in the solid residue owing to the low solubility of Ca(OH)2 in water. This approach also achieves minimal mass intensity, with 5.8 kg of reactants kg−1 of LA, with unnecessary reactant consumption.
PB Wiley
SN 1932-104X
YR 2025
FD 2025-04
LK http://hdl.handle.net/10259/10446
UL http://hdl.handle.net/10259/10446
LA eng
NO This work was supported by the Agencia Estatal de Investigación (grant numbers PID2022-136385OB-I00, TED2021-129311B-I00), the Junta de Castilla y León and the European Regional Development Fund (grant number BU027P23). A.E. Illera's postdoctoral contract was funded by BU027P23. H. Candela's pre-doctoral contract was funded by the Junta de Castilla y León and the European Social Fund (ORDEN EDU/1009/2024). P. Barea's pre-doctoral contract is funded by JCyL and the European Social Fund (ORDEN EDU/1868/2022).
DS Repositorio Institucional de la Universidad de Burgos
RD 09-may-2025