Preparation and characterization of MWCNT-TEPA/polyurethane nanocomposite membranes for CO2/CH4 separation: Experimental and modeling

Abstract

In the current study, multiwall carbon nanotubes (MWCNTs) were functionalized with Tetraethylene Pentamine (TEPA) and added into polyurethane (PU) polymer matrix to prepare PU-MWCNT-TEPA nanocomposite membranes. The prepared membranes were characterized using FT-IR, XRD and SEM analysis. The analysis results showed that MWCNTs were properly functionalized with TEPA and also uniformly dispersed in polymer matrix. The CO2 permeability increased by 99.8% at 10wt.% loading of MWCNTs-TEPA. The nanocomposite membrane’s CO2/CH4 selectivity was also increased by 9.6%. Impacts of operating pressure and temperature on the membranes’ CO2 permeability and CO2/CH4 ideal selectivity were also investigated. Finally, the gaseous penetrants permeabilities through the nanocomposite membranes were predicted using the Maxwell, the KJN, and the modified KJN models by AAREs of 31.4–35.2, 27.8–31.6, and 4.4–5.7%, respectively.