Aminosilane-Grafted Zirconia-Titiania-Silica Nanoparticles/TorIon Hollow Fiber Composites for CO2 Capture

In this work, the development of novel binary and ternary oxide/Torlon hollow fiber composites comprising zirconia, titania, and silica as amine supports was demonstrated. The resulting binary (Zr-Si/PAI-HF, Ti-Si/PAI-HF) and ternary (Zr-Ti-Si/PAI-HF) composites were then functionalized with monoamine-, diamine-, and triamine-substituted trialkoxysilanes and were evaluated in CO2 capture. Although the introduction of both Zr and Ti improved the CO2 adsorption capacity relative to that with Si/PAI-HF sorbents, zirconia was found to have a more favorable effect on the CO2 adsorption performance than titania, as previously demonstrated for amine sorbents in the powder form. The Zr-Ti-Si/PAI-HF sample with an oxide content of 20 wt% was found to exhibit a relatively high CO2 capacity, that is, 1.90 mmol g(-1) at atmospheric pressure under dry conditions, owing to more favorable synergy between the metal oxides and CO2. The ternary fiber sorbent showed improved sorption kinetics and long-term stability in cyclic adsorption/ desorption runs.