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  • Investigation of CO2 and Methanol Solubility at High Pressure and Temperature in the Ionic Liquid [EMIM][BF4] Employed During Methanol Synthesis in a Membrane-Contactor Reactor
Title: Investigation of CO2 and Methanol Solubility at High Pressure and Temperature in the Ionic Liquid [EMIM][BF4] Employed During Methanol Synthesis in a Membrane-Contactor Reactor
In this paper, the solubility properties of the ionic liquid (IL), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) were studied using a high-pressure, high-temperature set-up employing the pressure-drop technique. [EMIM][BF4] was selected for study because it is used as the sweep liquid in a membrane reactor (MR)-based methanol synthesis (MR-MeS) process recently proposed and studied by our group. The MR-MeS studies indicated high methanol (MeOH) solubilities in the IL under typical MeS reaction conditions, which then motivated this study to measure such solubilities directly under non-reactive conditions to validate the findings of the MR study. In addition, during the MR-MeS studies a concern existed about the solubility of CO2 in [EMIM][BF4], since it is a reactant in the MeS process and its dissolution in the sweep liquid would be detrimental for reactor performance. Studies, therefore, were also carried out to investigate the solubility of CO2, in addition to MeOH, in the IL. Our investigation indicates that though CO2 solubilities in the [EMIM][BF4] are high at room temperature, they become negligible at the typical MeS operating conditions (i.e., temperatures above 200 ⁰C).  more » « less
Award ID(s):
1705180
PAR ID:
10310514
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Chemical engineering science
Volume:
242
ISSN:
0009-2509
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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