(281e) Rapid Swing Adsorption/Desorption Using Polymer Supported Amine/Silica Hollow Fiber Sorbents for CO2 Capture

Rapid temperature swing adsorption/desorption (RTSA) using novel polymeric supported amine/silica hollow fiber sorbents represents a new approach to post combustion CO₂ capture [1]. Hollow fiber sorbent contactors function as a “nanoscopic heat exchangers,” where flue gas is fed through the shell-side of fiber module and heating/cooling media is fed through the bore. The unique structure of the porous hollow fiber sorbent allows coupling of efficient heat transfer with effective gas contacting, achieving essentially isothermal sorption while providing a lower parasitic load compared to a traditional fixed bed process. In this work, we report the synthesis and application of cellulose acetate/silica supported amine hollow fiber sorbents [2-4] that demonstrate high dynamic CO₂ capacities in the presence of water along with outstanding cyclic stability over 60 cycles. Additionally, robust dual layer polyamide-imide (PAI, Torlon^®, Solvay Advanced Polymers^©) silica supported amine hollow fiber sorbents (Torlon-S-PEI) were successfully developed as well, with the successful addition of impermeable lumen layer in the fiber spinning process [5]. A CO₂ breakthrough capacity of up to 1.33 mmol/g-fiber (2.66 mmol/g-silica) was observed when the first generation fibers were actively cooled by flowing cooling water in the fiber bores (with efficient heat removal), whereby the sorption enthalpy recovery can reach ~ 72%. Deactivated fibers were regenerated via post-spinning amine infusion, allowing recovery of the full sorption capacity of fiber sorbents after deactivation due to oxidation or poisoning by SO₂ or NO₂, The potential for significant savings in terms of energy, capital and operational costs exists with this scalable CO₂capture technique based on polymer/silica supported amine fiber sorbents.

1.         Lively, R.P., et al., Hollow fiber adsorbents for CO₂ removal from flue gas. Industrial & Engineering Chemistry Research, 2009. 48(15): p. 7314-7324.

2.         Labreche, Y., et al., Post-spinning infusion of poly(ethyleneimine) into polymer/silica hollow fiber sorbents for carbon dioxide capture. Chemical Engineering Journal, 2013. 221(0): p. 166-175.

3.         Rezaei, F., et al., Aminosilane-grafted polymer/silica hollow fiber adsorbents for CO₂ capture from flue gas. ACS Applied Materials & Interfaces, 2013. 5(9): p. 3921-3931.

4.         Fan, Y., et al., Evaluation of CO₂ adsorption dynamics of polymer/silica supported poly(ethylenimine) hollow fiber sorbents in rapid temperature swing adsorption. International Journal of Greenhouse Gas Control, 2014. 21(0): p. 61-71.

5.         Labreche, Y., et al., Dual layer spinning with lumen layer containing PAI/Silica/PEI hollow fiber sorbent for CO₂ separation by rapid temperature swing adsorption. In preparation.