The ionic liquid 1-ethyl-3-methylimidazolium dicyanamide, [C2mim]N(CN)2 is a suitable solvent for the extractive distillation of ethanol/water mixtures. This IL has comparable relative ethanol/water volatility as the benchmark solvent ethylene glycol (EG). Pilot plant experiments with both EG and [C2mim]N(CN)2 as solvent proved that the developed model for the extractive distillation of ethanol/water could well describe the experimental results. The achieved purity of the ethanol in the pilot plant using [C2mim]N(CN)2 as solvent was 99.91%. A conceptual process was designed for both the benchmark solvent EG and the IL. The process with the IL as solvent required 11% more energy than that with EG as solvent. However, if heat integration is implemented, the extractive distillation with the IL requires 16% less energy than the EG-based process. The key performance points for extractive distillation of ethanol/water mixtures are the recovery of the ionic liquid and the heat integration.
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