In this study a high-pressure membrane reactor (MR) was employed to carry-out the methanol synthesis (MeS) reaction. Syngas was fed into the MR shell-side where a commercial MeS catalyst was used, while the tube-side is swept with a high boiling point liquid with good solubility towards methanol. A mesoporous alumina ceramic membrane was utilized, after its surface had been modified to be rendered more hydrophobic. The efficiency of the MR was investigated under a variety of experimental conditions (different pressures, temperatures, sweep liquid flow rates, and types of sweep liquids). The results reveal improved per single-pass carbon conversions when compared to the conventional packed-bed reactor. An ionic liquid (IL), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) was utilized in the MR as the sweep liquid. The experimental results are compared to those previously reported by our Group (Li and Tsotsis, J. Membrane Sci., 2019) while using a conventional petroleum-derived solvent as sweep liquid, tetraethylene glycol dimethyl ether (TGDE). Enhanced carbon conversion (over the petroleum-derived solvent) was obtained using the IL.
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Methanol synthesis in a high-pressure membrane reactor with liquid sweep
Membrane reactors (MR) are known for their ability to improve the selectivity and yield of chemical reactions. In this paper, a novel high-pressure MR employing a liquid sweep was applied to the methanol synthesis (MeS) reaction, aiming to increase the per single-pass conversion. For carrying-out the reaction, an asymmetric ceramic membrane was modified with a silylating agent in order to render its pore surface hydrophobic. A commercial MeS catalyst was used for the reaction, loaded in the MR shell-side, while the tube-side was swept with a high boiling point organic solvent with high solubility towards methanol. The membrane reactor was studied under a variety of experimental conditions (different pressures, temperatures, space times, and liquid sweep flow rates) and showed improved carbon conversion when compared to the conventional packed-bed reactor operating under the same conditions.
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- Award ID(s):
- 1705180
- NSF-PAR ID:
- 10188054
- Date Published:
- Journal Name:
- Journal of membrane science
- Volume:
- 570-571
- ISSN:
- 0376-7388
- Page Range / eLocation ID:
- 103-111
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.memsci.2018.09.071
