Alcoholysis kinetics and mechanism studies of ethyl levulinate production from ball milled corn stover

Alcoholysis of High-Solid xylose residue for methyl levulinate preparation and its kinetics

Achieving the efficient biomass alcoholysis to methyl levulinate (ML) under high solid content conditions and establishing its kinetic model are crucial, but remain challenging. Here, the alcoholysis of microcrystalline cellulose (MC) and xylose residue (XR) to ML under high solid content conditions using CuSO4 as a catalyst was reported. High yield (34.96 wt%) and concentration (41.48 g/L) of ML from MC alcoholysis are achieved under the optimal conditions. Meanwhile, the yield and concentration of ML from XR alcoholysis can reach 26.73 wt% and 31.72 g/L, respectively. The alcoholysis pathways of MC and XR are proposed. A mixed model consisting of a shrinking core model and a pseudo-first-order kinetic model was established to elucidate the alcoholysis behavior of biomass. The generation of glucose is the rate-limiting step of the alcoholysis process, and there is no significant dependence between the activation energies of main reactions and the solid content of biomass.

Environmentally sustainable ethyl levulinate synthesis from delignified sugarcane bagasse using ternary eutectic solvent under MW-xenon irradiation: engine performance and emission assessment

For the first time, a synergistic energy-efficient combination of microwave-xenon (MW-XE) irradiations in presence of photoactive ternary acidic deep eutectic solvents (TADES) has been applied for intensification of ethyl levulinate synthesis from delignified sugarcane bagasse (DSB) under mild (90 min, 90 °C) and environmentally benign process conditions. The Taguchi orthogonal designed optimized conditions (20 W/cm3 of MW specific irradiation power input, 1 mol/mol of FeCl3 to citric acid ratio, 90 min of reaction time, 150 W of XE specific power input) rendered maximum 61.3 mol% of EL yield (selectivity: 87.70 ± 0.5%). Remarkably, synergistic effect of MW and XE irradiation significantly enhanced the EL yield (61.3 mol%) compared to the individual MW (34.52 mol%) and XE (22.67 mol%) irradiation at otherwise optimized reaction conditions. Moreover, the MWXE irradiated reactor (MWXER) exhibited a significant 79.10% increase in EL yield compared to the conventional thermal reactor (CTR), at the expense of 10% less energy consumption. The ethyl levulinate could be recovered efficiently through green protocol from reaction mix resulting in high purity (97 ± 0.5%) and TADES was sustainably reused in the process. The optimally generated product EL when blended (5 and 10 vol.%) with B10 and B20 (10% and 20% biodiesel-diesel blend) could provide 21-31% reduction in HC and 7.3-36% reduction in CO in comparison with petro-diesel. It was also explored that, at similar optimal parametric combinations, the TADES produced 29.5% greater EL yield in comparison with the standard ionic liquid BMIMCl. The life cycle environmental impact analysis (LCEIA) of the overall process revealed that the 5 vol.% EL blending with B10 contributed lowest environmental impacts mitigating marine ecotoxicity, human toxicity, fossil depletion, and climate change by 77.9%, 77.4%, 78.4% and 77.5%, respectively.