Abstract
A 6FDA based polyamide-imide, 6F-PAI-1, is compared to Pebax®, a commercially available rubbery polyether/polyamide block copolymer, for the simultaneous separation of CO2 and H2S from CH4. Feed streams of 20/20/60 and 5/45/50H2S/CO2/CH4 were used to compare the effect of acid gas concentration on the separation efficiency of 6F-PAI-1 and Pebax® under industrially relevant conditions. 6F-PAI-1 showed CO2/CH4 selectivities at 850psia total feed pressure of 30 and 40 for the 20/20/60 and 5/45/50 feed streams, respectively, while selectivity for H2S/CH4 was approximately 20 for both feeds. Pebax® showed selectivities of 40 and 10 for H2S/CH4 and CO2/CH4, respectively. Both selectivities were mostly independent of acid gas concentration in the feed, an unsurprising trend considering the non-glassy nature of this material. The selectivities in 6F-PAI-1 translated to less than 6% CH4 lost in the permeate stream for both feeds, while for the 5/45/50 feed, CH4 fraction in the permeate at 850psia was less than 4%. These promising results suggest that glassy polymers possessing favorable intrinsic plasticization resistance, such as 6F-PAI-1, may be appropriate for the typical case of natural gas sweetening where CO2 concentration in the feed is higher than it is for H2S. © 2014 Elsevier B.V.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 107-116 |
| Number of pages | 10 |
| Journal | Journal of Membrane Science |
| Volume | 465 |
| DOIs | |
| State | Published - Sep 2014 |
| Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): KUS11-011-21
Acknowledgements: This publication is based on work supported by Award no. KUS11-011-21, made by King Abdullah University of Science and Technology (KAUST). The authors would also like to thank Dr. Justin Johnson and Dr. (Viz Karvan for design and construction of the H2S equipment.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.