(352c) An Investigation into Electrospun Scaffolds Containing Ion-Exchange Resins for Direct Capture of CO2 from Ambient Air

The application of carbon capture for ambient air conditions, known as direct air capture, can be used to reduce emissions from nonlocalized sources. Although there is considerable research on materials for CO₂ capture, these are often expensive or difficult to prepare. Ion exchange resins are advantageous due to their high surface area, low cost and primarily their capability to be regenerated [1-4]. Using a water-driven reversible hydrolysis reaction, resins easily change affinity to CO₂ depending on the humidity in the environment. Regeneration of resins with water can reduce the costs associated with using temperature or pressure swing regeneration systems. In this study, we embed a commercially available Purolite A500 ion exchange resin within an electrospun ternary polymer mat of polystyrene, polyethylene oxide and polycaprolactone. The CO₂ adsorption performance of various loadings of Purolite A500 resin electrospun into fiber mats were analyzed through isothermal TGA analysis over a temperature range of 40 to 70°C. Characterization through IR, Microscopy, NMR, and SEM imaging was used to determine scaffold morphology. The Purolite A500 resin showed a CO₂ adsorption capacity of 0.0814 mmol/g and improved uptake resulting from electrospinning, with adsorption capacity of the embedded resin increasing by 42 - 109% at loadings of 16 - 32% w/w. Data obtained was fitted to a series of kinetic models and the Avrami’s fractional kinetic model was found to best fit the experimental data.

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