Title
Stability investigation of polyPOSS-imide membranes for H2 purification and their application in the steel industry
Author
Ansaloni, L.
Sarić, M.
Louradour, E.
Radmanesh, F.
Dijkstra, J.W.
Pilz, M.
Høvik, D.
Benes, N.E.
van Delft, Y.
Peters, T.A.
Publication year
2021
Abstract
In the present work, the high-temperature and long-term hydrothermal stability of novel polyPOSS-imide membranes for high-temperature hydrogen separation is investigated. The polyPOSS-imide membranes are found to exhibit an appropriate stability up to 300 °C. Above this temperature the membrane selectivity rapidly decreases, which is seemingly related to changes in the molecular structure coupled to silanol condensation forming siloxane groups. Surprisingly, the exposure of the membrane to temperatures of up to 300 °C even increases the H2 permeance together with the selective feature of the polyPOSS-imide layer. Subsequently, the long-term hydrothermal stability of the polyPOSS-imide membranes was investigated over a period of close to 1000 h at 250 °C exposing the membrane to 10 mol% steam in the feed. An increase in H2/CH4 selectivity was observed upon water addition, and even though a minor drop was noticed over time during the hydrothermal operation, the selectivity exceeds the initial selectivity obtained in the dry feed atmosphere. After the removal of steam from the feed the performance returns to its original state prior to the exposure to any steam showing an appropriate steam stability of the polyPOSS-imide membranes. A conceptual process design and assessment was performed for application of these membranes involving a combination of carbon reuse and electrification of the steel making process with co-production of hydrogen. The results indicate a CO2 avoidance of 14%. The CO2 reduction achieved using renewable electricity in the proposed scheme is a factor 2.76 higher compared to a situation where the same renewable electricity would be fed in the electricity grid.
Subject
Gas separation
Humidity
Hydrogen
Membrane
polyPOSS-imide
Stability
Air purification
Carbon dioxide
Gas permeable membranes
Hydrogen production
Steam
Steelmaking
CH 4-selectivity
Gas separations
Highest temperature
Hydrogen separation
Hydrothermal stabilities
Membrane selectivity
Polyposs-imide
Renewable electricity
Silanols
Water addition
Stability
To reference this document use:
http://resolver.tudelft.nl/uuid:58a4f72f-8d8b-47c8-879b-425848a1e65c
DOI
https://doi.org/10.1016/j.ijhydene.2021.09.089
TNO identifier
959448
Publisher
Elsevier Ltd
ISSN
0360-3199
Source
International Journal of Hydrogen Energy
Document type
article