MIL-101(Cr) Polymeric Fiber Adsorbents for Sub-Ambient Post-Combustion CO<sub>2</sub> Capture
Stephen J. A. DeWitt, Ryan P. Lively
Abstract
In this work, the development of a new metal–organic framework (MOF) fiber adsorbent for application to sub-ambient CO2 capture is discussed. MIL-101(Cr), a large pore (27 and 34 Å) MOF, provides unique advantages for this application as it has good water stability and high capacity for CO2 at sub-ambient conditions. The synthesis of MIL-101(Cr) was scaled to ∼20-g scales to facilitate fiber spinning, and the fibers were successfully manufactured up to 50 wt % loading of the MOF at rates up to 25 m/min. A variety of dynamic adsorption experiments, including sub-ambient fixed bed breakthroughs, high and ambient pressure helium-sweep desorption, and preliminary single-bed PSA cycles, were performed to better understand the performance of these fiber adsorbents for application to sub-ambient CO2 capture. Breakthrough and pseudoequilibrium capacities showed this promising fiber adsorbent retained its exceptionally high sub-ambient CO2 capacity under realistic PSA conditions, while desorption experiments showed there was some promise for the collection of a high-purity vacuum product in real cycles. Preliminary single-bed PSA cycles showed some promise while also proving much work needs to be done with cycle design to reach the required performance for post-combustion CO2 capture.