Synthesis and characterization of polydopamine-coated graphene oxide as a multifunctional filler for high-efficiency CO2 separation from flue gas

Abstract

ABSTRACT In the separation of CO2 from flue gas by membrane technology, the development of high permeability and selectivity, environmentally friendly and inherent merit materials play a vital role in efficient membrane processes. For this purpose, chemically active polydopamine (PDA) was successfully synthesized by solution-oxidation method and used in the functionalization and modification of graphene oxide (GO) and GO-polyethylene glycol (PEG) nanomaterial as bio-fillers were incorporated into polyethersulfone (PES) membrane as the basis of the fabricated mixed membrane matrix (MMM). The chemical, physical, thermal behavior and crystallographic structure of bio-fillers and membranes were studied by several analyses. The related functional groups are successfully obtained during the three steps of synthesis, including PEG-GO, PDA-PEG-GO and PDA-GO synthesis. The separation performance of the synthesized-MMM for 30% CO2/70% N2 gas mixture was studied, which resulted to the selectivity of 577.8 and permeability of 416.05 Barrer for PES-PDA-PEG-GO membrane under humidified condition. As a case study, the separation performance of MMM was evaluated for CO2 separation from a typical flue gas that resulted in a selectivity of 339.56 and permeability of 237.5 Barrer. According to the results obtained from a typical flue, the synthesized membrane has an acceptable potential for CO2 separation and industrial uses.