Characterization of Electrospun PAN Polymer Nanocomposite Membranes for CO2/N2 Separation

The focus of this study was to enhance the CO2 capture capabilities of polyacrylonitrile (PAN) nanocomposite membranes by reinforcing them with multi-walled carbon nanotubes (MWCNT) and silica (SiO2). These nanocomposite membranes were created using electrospinning technology, which produced nonwoven nanofiber membranes. The nanoparticles were functionalized using Gum Arabic (GA) to improve the distribution and prevent agglomeration. Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) analysis were conducted to examine the functionalization of nanoparticles and their morphological structures. The membranes were experimentally characterized to obtain the CO2 absorption properties and also to evaluate CO2/N2 permeation properties compared to pure PAN membranes. The results showed that higher nanoparticle concentrations increased CO2 permeability while maintaining stable N2 permeability, ensuring favorable CO2/N2 selectivity ratios. The 4 wt.% MWCNTs nanocomposite membrane achieved the best CO2/N2 separation with a CO2 permeability of 289.4 Barrer and a selectivity of 6.3, while the 7 wt.% SiO2 nanocomposite membrane reached a CO2 permeability of 325 Barrer and a selectivity of 7. These findings indicate significant improvements in CO2 permeability and selectivity for the nanocomposite membranes compared to pure PAN membranes. The Maxwell mathematical model has been used to validate the experimental results. The experimental results of the CO2 separation properties of the nanocomposite membranes exceeded the predicted values by the mathematical models. This might be due to the well-dispersed nanoparticles and functional groups.