Carbon nanotube-based mixed-matrix membranes with supramolecularly engineered interface for enhanced gas separation performance

March 13, 2020

Title

Carbon nanotube-based mixed-matrix membranes with supramolecularly engineered interface for enhanced gas separation performance

Author

Qinnan Zhang, Si Li, Ceming Wang, Hsueh-Chia Chang, Ruilan Guo

Year

2019

Journal

Journal of Membrane Science

Abstract

In this study, novel nanocomposite membranes were fabricated from single-walled carbon nanotubes (SWNTs) and a triptycene-containing polyimide. The desirable interfacial morphology and homogenous dispersion of SWNTs were achieved by strong π-π stacking and supramolecular shape-fitting interactions between the nanotube and the paddlewheel-shaped triptycene moieties in polymer matrix. Mixed-matrix membranes (MMMs) containing 2–15 wt% of as-purchased SWNTs (AP-SWNTs) were prepared and tested for their gas transport properties. While all MMMs showed greatly enhanced permeabilities with well-maintained selectivities, a non-linear dependence of permeability on filler content was observed. Another series of MMMs with purified SWNTs (P-SWNTs) and acid-treated SWNT (A-SWNTs) were also prepared. The functionalized A-SWNT MMM exhibited the best separation performance at 2 wt% filler content among all MMMs, which can be attributed to the improved interfacial affinity with carboxylic acid functionalized surface of A-SWNTs.

Instrument

NRS-5100

Keywords

Mixed-matrix membrane, Triptycene-containing polyimide, Single-walled carbon nanotubes, Gas separation