2026-09-13T20:58:20Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/109172025-10-03T00:05:23Zcom_10259_4244com_10259_5086com_10259_2604col_10259_4245

Candela Gil, Helena Illera Gigante, Alba Ester Barea Gómez, Pedro Beltrán Calvo, Sagrario Sanz Díez, Mª Teresa 2025-10-02T09:44:18Z 2025-10-02T09:44:18Z 2025-06 https://hdl.handle.net/10259/10917 10.3390/catal15060539 2073-4344 The lactic acid (LA) production from corn stover using Lewis acid catalysts was optimized. Initially, an equimolar mixture of Al(III)/Sn(II) was used as a catalytic system at 190 ◦C with 5 wt% biomass. Increasing the catalyst concentration led to higher LA production, showing the optimal results at 16 mM. A low catalyst concentration mainly produced furfural and HMF, dehydration products from the corn stover sugars. Higher catalyst concentration increased LA yield but also produced the degradation of the glucose dehydration products into levulinic and formic acids, reducing LA selectivity. Al(III) was essential for LA formation, while Sn(II) was less effective due to its lower solubility, shown by the presence of Sn(II) in the solid residue after treatments. A total of 16 mM Al(III) yielded the highest LA levels at 190 ◦C, 7.4 g/L, and 20.7% yield. Increasing the temperature to 210 ◦C accelerated the LA production while also achieving the lowest energy consumption, which was 0.47 kWh/g LA at the highest LA production point. However, longer treatments at this temperature caused LA degradation. AlCl3 has been identified as an ideal catalyst for biomass conversion to LA, being inexpensive and low in toxicity. This research was funded by the Agencia Estatal de Investigación, grant numbers PID2022-136385OB-I00 and TED2021-129311B-I00, and the Junta de Castilla y León (JCyL) and the European Regional Development Fund (ERDF), grant numbers BU027P23. A.E. Illera’s post-doctoral contract was funded by BU027P23. H. Candela’s pre-doctoral contract was funded by JCyL and the European Social Fund [ORDEN EDU/1009/2024]. P. Barea’s pre-doctoral contract is funded by JCyL and the European Social Fund (ESF) [ORDEN EDU/1868/2022]. application/pdf eng MDPI Catalysts. 2025, V. 15, n. 6, 539 https://doi.org/10.3390/catal15060539 Atribución 4.0 Internacional http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Al(III)/Sn(II) Lactic acid Corn stover Subcritical water Organic acids Ácido láctico Lactic acid The Study and Optimization of the AlCl3/SnCl2 Catalyst System in the Subcritical Water Production of Lactic Acid from Corn Stover info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Catalysts 15 6 539