Energy-efficient bioethanol recovery process using deep eutectic solvent as entrainer.

Bioethanol is commonly recovered from fermentation broth via distillation because it is the most economical and reliable process for large-scale industrial operations. Because extraction is a highly energy-efficient process applicable to low-composition bio-product separation, high-performance solvents are necessary for efficient bioethanol recovery. 2-Methyl pentanol, a branched long-chain alcohol, which was used as the extraction solvent, and a deep eutectic solvent, choline chloride and ethylene glycol (1:2), was employed as an entrainer for product refinement. Thermodynamic models of vapor–liquid equilibrium (VLE) and liquid–liquid equilibrium (LLE) systems were derived using molecular simulations and experimental results to develop the bioethanol extraction and refinement processes. The heat duty of the designed process was reduced by a quarter compared to that of previous recovery processes. [ABSTRACT FROM AUTHOR]