Carbon dioxide capture using an omniphobic membrane for a gas-liquid contacting process

Abstract

An omniphobic membrane has been successfully prepared to ensure high efficiency as well as long-term stability in a CO 2 absorption process. This omniphobic membrane was fabricated by creating a multilevel re-entrant structure via depositing ZnO nanoparticles (NPs) on a porous glass fiber (GF) membrane through chemical bath deposition (CBD). The membrane coated with ZnO NPs was then functionalized with 1 H,1 H,2 H,2H-perfluorodecyltriethoxysilane (FAS17) and coated with a polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) polymer. A variety of techniques such as capillary flow porometry (CFP), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), contact angle goniometry, atomic force microscope (AFM) and CO 2 absorption trials were conducted to explore the surface structure, chemistry and performance of the membrane. The omniphobic membrane surface with a high fluorine concentration had a strong resistance to wetting by water and organic liquids (£^ = 72.8¡V22.1 mN/m) and showed a contact angle with an amine absorbent as high as 147.8 ¡Ó 0.8¢X. In the CO 2 absorption trials, the omniphobic membrane exhibited a stable absorption flux of 2.10 ¡Ó 0.07 mmol/m 2 s for 96 h. The results indicate that the omniphobic membrane outperforms hydrophobic membranes. Thus, the omniphobic membrane has shown potential for application in large-scale CO 2 absorption in thermal power plants. ? 2018 Elsevier B.V.