RT journal article
T1 Bioethanol production from sugar beet pulp dark fermentation residues: A cascade biorefinery and kinetic modelling approach
A1 Witz-Aquino, Lethicia
A1 Gómez Quiroga, Xiomara
A1 Romero Vargas, Agustín
A1 Blandino Garrido, Ana María
A1 Romero García, Luis Isidoro
A2 Ingeniería Química y Tecnología de Alimentos
K1 Sugar beet pulp
K1 Dark fermentation residue
K1 Bioethanol
K1 Cascade biorefinery
K1 Kinetic modelling
K1 Synergistic inhibition
AB The transition to a circular bioeconomy requires the complete valorisation of agro-industrial side-streams through zero-waste cascading biorefineries. This study investigates the conversion of the solid residue from dark fermentation (SRDF), a byproduct of biohydrogen and organic acid production from sugar beet pulp, into bioethanol. Compositional analysis revealed that dark fermentation acts as an effective biological pretreatment, significantly increasing the accessibility of the lignocellulosic matrix by removing amorphous fractions. Enzymatic saccharification of SRDF achieved a glucose yield of 83.33%, nearly doubling the 47.36% yield obtained from raw pulp. To enhance volumetric productivity, a co-fermentation strategy using sugar beet molasses was evaluated. While pure SRDF hydrolysates demonstrated high biocompatibility, supplementation with 30% w/w molasses triggered a stuck fermentation profile, leaving significant residual fructose. A hybrid logistic-Monod kinetic model was developed to elucidate these interactions. The model identified a 45% reduction in microbial carrying capacity (Xmax) caused by the synergistic inhibitory effect of high mineral salt concentrations from molasses and residual organic acids from the dark fermentation stage. These findings establish critical operational limits for co-substrate utilization and provide a mechanistic framework for optimising second-generation sugar beet biorefineries.
PB Elsevier
SN 1873-2909
YR 2026
FD 2026-11-04
LK http://hdl.handle.net/10498/40580
UL http://hdl.handle.net/10498/40580
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 10-nov-2026