The valorization of agri-food biomass offers a promising pathway for sustainable bioproduct
generation, aligning with circular economy principles. This study investigates the production of
lactic acid (LA) through the subcritical water hydrolysis (SWH) of selected agrifood residues,
followed by its separation using micro- (MF) and nanofiltration (NF). Agri-food residues rich in
hemicelluloses, such as corn stover, were subjected to SWH in the presence of heterogeneous
catalysts such as Yb 3+ salts [1] and Ca(OH)2) to maximize LA yield, achieving concentrations of
up to 14.4 g/L under optimized reaction conditions. The subsequent NF process employed
membranes with varying molecular weight cut-offs to assess LA recovery efficiency, flux, and
rejection rates. Membrane fouling and the influence of operating parameters such as pressure and
feed concentration were also evaluated using synthetic solutions. The optimal NF configuration
achieved good LA concentration with minimal co-product contamination, demonstrating the
potential for effective LA purification. This integrated approach not only addresses the disposal
challenges associated with agrifood residues but also provides a sustainable route for high-value
LA production. The findings underscore the feasibility of coupling SWH and membrane
technology for lactic acid production and recovery, contributing to resource-efficient agricultural
practices and waste valorization.
