Journal of Membrane Science & Technology

Hydroxyl-functionalized triptycene-based polyimide membrane for CO2 separation and reservoir reinjection for enhanced oil recovery processes

2^nd International Conference on Membrane Science and Technology

September 13-14, 2018 | London, UK

Fahd Alghunaimi, Bader Ghanem, Nasser Alaslai and Ingo Pinnau

EXPEC Advanced Research Center, Saudi Arabia
King Abdullah University of Science and Technology (KAUST), Saudi Arabia

Posters & Accepted Abstracts: J Membr Sci Technol

Abstract:

Novel triptycene-based polyimides showed promising results to be candidate membrane materials for removal of CO2 from natural gas, specifically for enhanced oil recovery applications. The gas permeation properties of two novel PIM-polyimides (TDA1-DMN) and (TDA1-APAF) prepared from 9,10-dimethyl-2,3,6,7-triptycene tetracarboxylic dianhydride (TDA1) with commercially available 3,3'-dimethylnaphthidine (DMN) and 2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (APAF) diamine monomers are reported. The triptycene building block with bridgehead methyl side groups provides TDA1-DMN with high BET surface area and very high gas permeabilities (CO2 = 3700 Barrer) but with only moderate selectivities (CO2/ CH4 selectivity = 17). An ortho-hydroxyl-functionalized polyimide (TDA1-APAF) was designed to enhance selectivities, while maintaining high gas permeability. TDA1-DMN and TDA1-APAF had BET surface areas based on nitrogen adsorption of 760 m2 g-1 and 260 m2 g-1, respectively. A freshly prepared sample of TDA1-APAF exhibited excellent gas permeation properties: H2 permeability of 94 Barrer with H2/CH4 selectivity of 129 and CO2 permeability of 40 Barrer coupled with CO2/ CH4 selectivity of 55. Physical aging over 250 days resulted in enhanced H2/CH4 selectivity of 183 with only ~25% loss in H2 permeability. Aged TDA1-APAF exhibited 5-fold higher pure-gas CO2 permeability (30 Barrer) and 2-fold increase in CO2/CH4 permselectivity (~75) over conventional dense cellulose triacetate membranes at 2 bar. Gas mixture permeation experiments (Figure 1) for fresh and aged films of TDA1-APAF with a 1:1 CO2/CH4 feed mixture demonstrated higher mixed-than puregas selectivity (~88) at 2.0 bar and plasticization resistance up to 30 bar. Moreover, the aged membrane exhibited N2/CH4 selectivity of 2.3 which potentially offers the opportunity of simultaneous removal of N2 and CO2 for natural gas upgrading. The obtained properties makes TDA1-APAF polyimide an excellent candidate material for development of asymmetric or thin film composite membranes for industrial natural gas sweetening or CO2 removal from natural gas for enhanced oil recovery processes.

Biography :

E-mail: fahad.alghuanimi@kaust.edu.sa