CO<sub>2</sub> separation of a novel Ultem‐based mixed matrix membrane incorporated with Ni<sup>2+</sup>‐exchanged zeolite X
Kimiya Nematolahi, Ehsan Salehi, Abtin Ebadi Amooghin, Hamidreza Sanaeepur
Abstract
Abstract In this study, polyetherimide (Ultem) was chosen as a polymeric matrix, and micron‐sized Ni 2+ ‐exchanged nano‐porous NaX zeolite was selected as an inorganic filler to fabricate novel mixed matrix membranes (MMMs) for CO 2 separation. Fabricated membranes were evaluated by Differential scanning calorimeter, Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, and energy dispersive X‐ray. The influences of filler loading (0–5 wt.%) and feed pressure (2–10 bar) on gas separation properties were surveyed. CO 2 /N 2 ideal selectivity of 3 wt.% NiX loaded MMM (optimum MMM) was increased to 34 (about 36%) compared to 25 for the pristine membrane. Furthermore, CO 2 permeability was improved by about 45%, from 1.3 Barrer for the pure membrane to 1.88 Barrer for MMM containing 3 wt.% functionalized filler. These improvements originate from a combination of the inherent surface diffusion mechanism of zeolite X and reversible reaction between free orbitals of transition metal ions (Ni 2+ ) and electron pairs of CO 2 molecules. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.