Separation of Linalool from Limonene via Extractive Distillation with 1-Butyl-3-methylimidazolium Acetate as Entrainer

Abstract

Orange processing generates a high amount of waste rich in natural compounds that can be used to obtain added-value products or as raw material in biorefineries. Limonene (terpene) and linalool (oxygenated terpene) stand out among those bioproducts due to their organoleptic, antioxidant, and preservative properties. They are widely used in the food, cosmetic, and chemical industries, but their use as generally recognized as safe solvents is also gaining interest. In this work, separation of a mixture of limonene and linalool is proposed by extractive distillation with the ionic liquid 1-butyl-3-methylimidazolium acetate. To that aim, isobaric vapor–liquid equilibrium at 5 kPa was determined for the binary and ternary systems involved, and the data were successfully correlated with the NRTL and UNIQUAC models. The process was simulated, and the recovery of the ionic liquid was tested with a flash unit at very low pressure (0.1 kPa) or a stripping column (5 stages, 101.32 kPa) with air at the maximum operating temperature and a gas–liquid separator (101.32 kPa, 298.15 K). In the second case, an extractive column with an entrainer flow rate of 100 kg/h, number of stages N = 20, and reflux ratio R = 0.5 allows the separation of practically pure limonene and linalool.

Bioproducts from agro-industrial plant residues: opportunities for sustainable reuse / Bioprodutos de resíduos agroindustriais vegetais: oportunidades ao reaproveitamento sustentável

“…Acai Seed Production of levulinic acid, formic acid and bioenergy by hydrolysis and fermentation. Ciriminna et al 2018;da Silva et al 2020b;Debernardi-Vázquez et al 2020;Fidalgo et al 2016;Ganen et al 2020;Kammoun et al 2020;Nicoletti et stability in high ionic strength and the use of alternative substrates in production by fermentation (Felipe and Dias 2017).…”

Evaluation of Ionic Liquids for the Sustainable Fractionation of Essential Oils

“…Even though EOs are abundant sources of many value-added monoterpenes, the literature addressing separation and purification technologies to obtain terpenes from their natural matrices is somehow scarce . And even though the use of ILs as separation agents in liquid–liquid extraction ,, or extractive distillation , processes has been investigated, most studies focus only on the deterpenation of citrus EOs, represented by limonene/linalool binary mixture. Nevertheless, the results found in this study and previous studies from our group , suggest that some ILs are potential separating agents to fractionate terpene mixtures found in the diverse EOs, such as citronellal/geraniol, eucalyptol/linalool, camphor/borneol, menthone/menthol, and p -cymene/carvacrol.…”

“…Ionic liquids are promising candidates to replace traditional organic solvents as separation agents in the extraction, isolation, and purification of biomolecules, having been extensively studied in those fields in the last few years . Besides their appealing properties, such as low volatility, great solvation ability, and excellent thermal stability, , these solvents can be tailored by combining different cations and anions, to reach specific physicochemical properties, expanding their range of applications. , Within the scope of terpene separation and purification, the potentialities of imidazolium ILs to produce terpeneless citrus EOs have been extensively investigated by Soto and co-authors. − Besides, imidazolium and phosphonium-based ILs showed the potential to fractionate several monoterpene/monoterpenoid mixtures present in different EOs. , Recently, deep eutectic solvents (DES) have also been pointed out as potential alternatives to fractionate citrus EOs. − …”

Liquid–Liquid Equilibrium Experiment and Mechanism Study on the System of Dimethyl Carbonate + n-Propanol + Ionic Liquids

“…7−9 To save cost, it is necessary to recover dimethyl carbonate and npropanol, which can form an azeotrope. Separating azeotropes require some special distillation methods, such as azeotrope distillation, 10 pressure swing distillation, 11 liquid−liquid extraction, 12,13 extractive distillation, 14,15 and membrane separation. 16,17 Liquid−liquid extraction can be carried out under atmospheric temperature and pressure and has the advantages of low energy consumption, high separation efficiency, large processing capacity, and high recovery rate.…”

“…DMC is used as a raw material to synthesize carbonates with different structures, such as dipropyl carbonate, diphenyl carbonate, isonitrile ester, glycerol carbonate, carbamate, and so on. , While synthesizing dipropyl carbonate, the products contain some dimethyl carbonate and n -propanol. − To save cost, it is necessary to recover dimethyl carbonate and n -propanol, which can form an azeotrope. Separating azeotropes require some special distillation methods, such as azeotrope distillation, pressure swing distillation, liquid–liquid extraction, , extractive distillation, , and membrane separation. , …”