Multilevel Comparison of Ionic Liquid Separation of a Methanol/Methyl Acetate/Water Mixture

Abstract

This paper aimed to investigate whether ionic liquids (ILs) with excellent phase equilibrium abilities were also economically superior at the process level. Comprehensive comparisons of seven different types of ILs for the separation of a methanol/methyl acetate/water mixture were performed from molecular, phase equilibrium, to the process level. The validated NRTL model was used for phase equilibria and process simulation and COSMO-based sigma profiles for mechanism analysis. Energy consumption, energy cost, and total annual cost (TAC) were carried out to quantify process performances. Heat pump-assisted IL-extractive distillation processes were proposed. The results indicated that the heat pump-assisted schemes saved the TAC up to 51.2%. The process economic performances of 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]), 1-hexyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium methylsulfate, and 1-ethyl-3methylimidazolium thiocyanate were equally well, while that of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide was the worst at all levels. The TAC savings of the [EMIM][Ac] process ranged from 3.4 to 48.2% compared with the latter six ILs. The order of performance of ILs in terms of relative volatility or binary phase diagram was nearly the same as the process level, while using the minimum amount of ILs required to break azeotropes as an indicator was of a different order.

Economic Analysis and Life Cycle Environmental Assessment of Imidazolium-Based Ionic Liquids for Separation of the Methanol/Dimethyl Carbonate Azeotrope

“…Aspen Plus V11 software was used for simulation and optimization of extractive distillation processes, of which the distillation columns were modeled by the RadFrac model, and the simulation method was based on the NRTL equilibrium. Total utility consumption (TUC), total energy cost (TEC), and total annual costs (TAC), i.e., 3 T, were used to evaluate the process performance …”

“…The basis of comparisons of the y – x phase diagrams was based on the molar fraction of the entrainers being 0.5 at 100 kPa. The degree of the y – x curve deviates from the diagonal line (Δ y ), which was used to express y – x phase diagram performance and calculated as follows: normalΔ y AP = | y LC ILs − y LC AC | where y LC AC refers to the vapor mole fraction of the light component at the azeotropic composition. When the light component was DMC, its value was 0.8529, and when the light component was methanol, its value was 0.1471. y LC ILs represents the vapor mole fraction of the light component with an IL mole fraction of 0.5, of which the corresponding liquid mole fraction of MA is at the azeotropic composition.…”

“…Total utility consumption (TUC), total energy cost (TEC), and total annual costs (TAC), i.e., 3 T, were used to evaluate the process performance. 53 LCA Approach. The "cradle to gate" LCA approach was carried out to evaluate the environmental impacts of the IL EDS for separating DMC/methanol azeotropes.…”

Elucidating the Ionic Liquid-Induced Mixed Inhibition of GH1 β-Glucosidase H0HC94

“…17 tions have shown that IL separation of a methanol/methyl acetate/water mixture using [C 2 C 1 im][MeCO 2 ] performs comparably to other ILs such as 1-hexyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium methylsulfate, and 1ethyl-3-methylimidazolium thiocyanate (1-ethyl-3-methylimidazolium thiocyanate. 19 Thus, [C 2 C 1 im][MeCO 2 ] continues to be a promising candidate as a model IL in the field of lignocellulosic biofuels and industrial applications. However, one downside of pretreating lignocellulose biomass with ILs is that the structure and function of the glycoside hydrolases (GHs) are considerably affected in the presence of residual ILs, resulting in a loss of enzymatic activity during the hydrolysis process.…”

“…Furthermore, enzymatic production of p -hydroxybenzaldehyde from Miscanthus using recycled diluted [C 2 C 1 im]­[MeCO 2 ] has been reported . Economic evaluations have shown that IL separation of a methanol/methyl acetate/water mixture using [C 2 C 1 im]­[MeCO 2 ] performs comparably to other ILs such as 1-hexyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium methylsulfate, and 1-ethyl-3-methylimidazolium thiocyanate (1-ethyl-3-methylimidazolium thiocyanate . Thus, [C 2 C 1 im]­[MeCO 2 ] continues to be a promising candidate as a model IL in the field of lignocellulosic biofuels and industrial applications.…”