Abstract
Continuous drying processes using supercritical CO2 (scCO2) as a water extraction agent require 24/7 operational dehydration units for scCO2 regeneration. Dehydration units using dense polymeric membranes are considered a cost effective, sustainable alternative to the current zeolite-based units. The focus of previous studies on the membrane-based dehydration of scCO2 was always on the membrane itself whereas boundary layer effects, e.g., concentration polarization, were not taken into account. To quantify the boundary layer effects, simulations were performed using three different membrane materials: SPEEK, Nafion® 117, and PEBAX® 1074. Process conditions during the simulations ranged from 8.0 to 18.0 MPa and 40 to 100 °C. Even though the three types of membranes examined differ in their H2O permeability and H2O over CO2 selectivity, in all cases 80% of the total mass-transfer resistance can be assigned to concentration polarization effects, making it the dominant parameter for water transport. Despite high but differing intrinsic water permeabilities of all three membranes materials, the H2O transport, thus H2O flux through the membrane is significantly reduced by concentration polarization down to similar levels. This makes it necessary to use larger membrane areas, that result in higher CO2 fluxes. As a consequence, material selection is predominantly based on the ability to reject CO2. Optimization of process conditions other than membrane material is briefly discussed.
| Original language | English |
|---|---|
| Pages (from-to) | 229-237 |
| Number of pages | 9 |
| Journal | Separation and Purification Technology |
| Volume | 209 |
| DOIs | |
| Publication status | Published - 31 Jan 2019 |
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Keywords
- Carbon dioxide
- Concentration polarization
- Gas separation
- Membranes
- Supercritical fluids
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Mass transfer studies on the dehydration of supercritical carbon dioxide using dense polymeric membranes. / Shamu, Andrew; Miedema, Henk; Metz, Sybrand J.; Borneman, Zandrie; Nijmeijer, Kitty (Corresponding author).
In: Separation and Purification Technology, Vol. 209, 31.01.2019, p. 229-237.Research output: Contribution to journal › Article › Academic › peer-review
TY - JOUR
T1 - Mass transfer studies on the dehydration of supercritical carbon dioxide using dense polymeric membranes
AU - Shamu, Andrew
AU - Miedema, Henk
AU - Metz, Sybrand J.
AU - Borneman, Zandrie
AU - Nijmeijer, Kitty
PY - 2019/1/31
Y1 - 2019/1/31
N2 - Continuous drying processes using supercritical CO2 (scCO2) as a water extraction agent require 24/7 operational dehydration units for scCO2 regeneration. Dehydration units using dense polymeric membranes are considered a cost effective, sustainable alternative to the current zeolite-based units. The focus of previous studies on the membrane-based dehydration of scCO2 was always on the membrane itself whereas boundary layer effects, e.g., concentration polarization, were not taken into account. To quantify the boundary layer effects, simulations were performed using three different membrane materials: SPEEK, Nafion® 117, and PEBAX® 1074. Process conditions during the simulations ranged from 8.0 to 18.0 MPa and 40 to 100 °C. Even though the three types of membranes examined differ in their H2O permeability and H2O over CO2 selectivity, in all cases 80% of the total mass-transfer resistance can be assigned to concentration polarization effects, making it the dominant parameter for water transport. Despite high but differing intrinsic water permeabilities of all three membranes materials, the H2O transport, thus H2O flux through the membrane is significantly reduced by concentration polarization down to similar levels. This makes it necessary to use larger membrane areas, that result in higher CO2 fluxes. As a consequence, material selection is predominantly based on the ability to reject CO2. Optimization of process conditions other than membrane material is briefly discussed.
AB - Continuous drying processes using supercritical CO2 (scCO2) as a water extraction agent require 24/7 operational dehydration units for scCO2 regeneration. Dehydration units using dense polymeric membranes are considered a cost effective, sustainable alternative to the current zeolite-based units. The focus of previous studies on the membrane-based dehydration of scCO2 was always on the membrane itself whereas boundary layer effects, e.g., concentration polarization, were not taken into account. To quantify the boundary layer effects, simulations were performed using three different membrane materials: SPEEK, Nafion® 117, and PEBAX® 1074. Process conditions during the simulations ranged from 8.0 to 18.0 MPa and 40 to 100 °C. Even though the three types of membranes examined differ in their H2O permeability and H2O over CO2 selectivity, in all cases 80% of the total mass-transfer resistance can be assigned to concentration polarization effects, making it the dominant parameter for water transport. Despite high but differing intrinsic water permeabilities of all three membranes materials, the H2O transport, thus H2O flux through the membrane is significantly reduced by concentration polarization down to similar levels. This makes it necessary to use larger membrane areas, that result in higher CO2 fluxes. As a consequence, material selection is predominantly based on the ability to reject CO2. Optimization of process conditions other than membrane material is briefly discussed.
KW - Carbon dioxide
KW - Concentration polarization
KW - Gas separation
KW - Membranes
KW - Supercritical fluids
UR - http://www.scopus.com/inward/record.url?scp=85050112121&partnerID=8YFLogxK
U2 - 10.1016/j.seppur.2018.07.042
DO - 10.1016/j.seppur.2018.07.042
M3 - Article
AN - SCOPUS:85050112121
VL - 209
SP - 229
EP - 237
JO - Separation and Purification Technology
JF - Separation and Purification Technology
SN - 1383-5866
ER -