Innovative eco-friendly hydroxyethylcellulose matrix-based composite for enhanced gas separation: Insights from performance and structural characterization.

With increasing concern for the environment, the demand for carbon dioxide separation, a key contributor to global warming, has escalated. Therefore, this paper focuses on carbon dioxide separation by creating an hydroxyethyl cellulose (HEC)(CHO)*(CHO(OH))/silver tetra fluoroborate (AgBF)/aluminum nitrate (Al(NO)) composite film, demonstrating excellent separation performance with a permeance of 1.0 GPU and a selectivity of 100. Silver ions enhance the solubility of carbon dioxide, aiding in its separation, and we determined the optimal aluminum composition to stabilize the silver ions. To analyze this, we examined the cross-sections using SEM, confirming a selective layer of 1.7 μm for carbon dioxide separation. Furthermore, TGA, FT-IR, and NMR analyses were conducted to investigate the interaction between the polymer and additives. This revealed that the increased polymer chain due to the interaction between Ag and HEC, along with stabilized Ag facilitated by the addition of Al, maximized the interaction with carbon dioxide via the empty s-orbital. Additionally, SEM-EDX, UV-vis, XRD, XPS analyses were employed to elucidate the movement of ions within the membrane. These results provide insights into the performance of membranes based on cellulose polymer and offer valuable insights for future applications in gas separation technologies.