Fabrication and characterization of poly(vinylidene fluoride)–polytetrafluoroethylene composite membrane for CO₂ absorption in gas–liquid contacting process

Abstract

The wetting resistance of poly(vinylidene fluoride) (PVDF) membrane is a critical factor which determines the carbon dioxide (CO 2 ) absorption performance of the gas-liquid membrane contactors. In this study, the composite PVDF-polytetrafluoroethylene (PTFE) hollow fiber membranes were fabricated through dry-jet wet phase-inversion method by dispersing PTFE nanoparticles into PVDF solution and adopting phosphoric acid as nonsolvent additive. Compared with the PVDF membrane, the composite membranes presented higher CO 2 absorption flux due to their higher effective surface porosity and surface hydrophobicity. The composite membrane with addition of 5 wt % PTFE in the dope gained the optimum CO 2 absorption flux of 9.84 × 10 −4 and 2.02 × 10 −3 mol m −2 s −1 at an inlet gas (CO 2 /N 2 = 19/81, v/v) flow rate of 100 mL min −1 by using distilled water and aqueous diethanolamine solution, respectively. Moreover, the 5% PTFE membrane showed better long-term stability than the PVDF membrane regardless of different types of absorbent, indicating that polymer blending demonstrates great potential for gas separation.

Dissolved oxygen from microalgae-gel patch promotes chronic wound healing in diabetes

“…The alga-gel was encapsulated by a sterile and 0.22-m porous polytetrafluoroethylene membrane as inner lining (36) and a transparent polyurethane film as back lining to manufacture AGP.…”