Title : Vapor-liquid equilibria of furfural with -Valerolactone or -Butyrolactone for biorefinery applications
Abstract:
Furfural, obtained from lignocellulosic biomass, is considered a key platform molecule due to its reactive and versatile structure. It consists of a furan ring and an aldehyde functional group, which confer high chemical reactivity. Consequently, furfural serves as a precursor to numerous chemical products essential in various fields, including pharmaceuticals, fine chemicals, biofuels, and polymer industries.
Similarly, g-valerolactone and g-butyrolactone are biomass-derived compounds. They are widely used as solvents owing to their polarity, complete miscibility with water and many organic solvents, and, above all, their non-toxic and biodegradable nature, which makes them environmentally friendly "green" solvents. Moreover, lactones are known to enhance biorefining reactions by increasing the
rate of furfural formation when used as solvents and by limiting the polymerization of furfural in the aqueous phase; a phenomenon that significantly reduces production yields.
The final step in furfural production is its extraction from the reaction medium (furfural–solvent mixture) by distillation. Reliable vapor–liquid equilibrium (VLE) data are essential for optimizing this separation process. However, data for furfural–lactone systems are scarce in the open literature; only the isobaric binary system furfural + g-valerolactone at 30 kPa has been reported by Pokki et al. This study extends the available data to lower pressures and temperatures for the furfural + g-valerolactone system and provides, for the first time, VLE data for the binary system furfural + g-butyrolactone, a homologous solvent to g-valerolactone.
The investigated temperature and pressure ranges for the pure compounds and binary systems were 283-363 K and 5-10 000 Pa, respectively. For the pure compounds, experimental data were in very good agreement with literature values. For the binary systems, no prior VLE data were available for comparison. The experimental results were correlated using the NRTL and UNIQUAC activity coefficient models, yielding parameters valuable for the design and optimization of separation processes.
