Separation of azeotropic mixtures using hyperbranched polymers or ionic liquids

Abstract

In this work the suitability of selected commercially available hyperbranched polymers and ionic liquids as entrainers for the extractive distillation and as extraction solvents for the liquid–liquid extraction is investigated. Based on thermodynamic studies on the influence of hyperbranched polymers and ionic liquids on the vapor–liquid and liquid–liquid equilibrium of the azeotropic ethanol–water and THF–water systems, process simulations are carried out, which allow evaluating the potential of hyperbranched polymers and ionic liquids as selective components for the mentioned applications in terms of feasibility and energetic efficiency. Both hyperbranched polymers and ionic liquids break a variety of azeotropic systems. Since their selectivity, capacity, viscosity, and thermal stability can be customized, they appear superior to many conventional entrainers and extraction solvents. For the ethanol–water separation, the nonvolatile substances hyperbranched polyglycerol and [EMIM]+[BF4]− show a remarkable entrainer performance and therefore enable extractive distillation processes, which require less energy than the conventional process using 1,2‐ethanediol as an entrainer. Evaluation of a new THF–water separation process indicates the competitiveness of the suggested process and a considerable potential of using hyperbranched polymers as extraction solvents. © 2004 American Institute of Chemical Engineers AIChE J 50: 2439–2454, 2004

Novel pressure and temperature swing processes for CO2 capture using low viscosity ionic liquids

“…For the sake of a fair comparison in terms of energy consumption and investments between the [C 6 mim][TCM]-and the Selexol-based processes, initially the same process flowsheet is 4 were purchased from Linde Gas Benelux B.V. with a purity of 99.995% and > 99.99%, respectively. The vapor-liquid equilibrium for the absorption process was modeled using the non-random two liquids (NRTL) model by Renon and Prausnitz [20] with the assumption (for simplicity) that the IL does not dissociate [21]. Gebbie et al [22] verified this assumption by combining direct surface force measurements with thermodynamic arguments.…”

“…The non-volatility of the IL was taken into account by setting the fitting parameter of the extended Antione equation to a negligible small value (1e −20 ), a similar procedure was used by Seiler et al [21]. Fig.…”

Ionic Liquids in Chemical Analysis

“…Ionic liquids have been found (29) 4 ] shows a remarkable entrainer performance and therefore can enable extractive distillation processes which require less energy than the conventional process using 1,2-ethanediol as an entrainer. In − ) gave high distribution ratios for aromatic solutes, especially chlorobenzenes, between the RTIL and water.…”

Liquid–Liquid Equilibria of Water + Ethanol + 1-Butyl-3-methylimidazolium Bis(trifluoromethanesulfonyl)imide Ternary System: Measurements and Correlation at Different Temperatures

“…For this reason, the elimination of the azeotrope was investigated with the use of ionic liquids (ILs) as entrainers for the extractive distillation [4][5][6] .…”