Graphene-Coated PVDF Membranes: Effects of Multi-Scale Rough Structure on Membrane Distillation Performance

Emilia Gontarek-Castro; Giuseppe Di Luca; Marek Lieder; Annarosa Gugliuzza

doi:10.3390/membranes12050511

Graphene-Coated PVDF Membranes: Effects of Multi-Scale Rough Structure on Membrane Distillation Performance

Membranes (Basel). 2022 May 10;12(5):511. doi: 10.3390/membranes12050511.

Authors

Emilia Gontarek-Castro¹, Giuseppe Di Luca², Marek Lieder¹, Annarosa Gugliuzza²

Affiliations

¹ Department of Process Engineering and Chemical Technology, Faculty of Chemistry, Gdansk University of Technology, 11/12 G. Narutowicza St., 80-233 Gdansk, Poland.
² Research Institute on Membrane Technology, CNR-ITM, Via Pietro Bucci 17/C, 87036 Rende, Italy.

Abstract

Graphene-coated membranes for membrane distillation have been fabricated by using a wet-filtration approach. Graphene nanoplatelets have been deposited onto PVDF membrane surfaces. Morphology and physicochemical properties have been explored to evaluate the changes in the surface topography and related effects on the membrane performance in water desalination. The membranes have been tested in membrane distillation plants by using mixtures of sodium chloride and humic acid. The multi-scale rough structure of the surface has been envisaged to amplify the wetting and fouling resistance of the graphene-coated membranes so that a better flux and full salt rejection have been achieved in comparison with pristine PVDF. Total salt rejection and an increase of 77% in flux have been observed for coated membrane with optimized graphene content when worked with NaCl 0.6 M (DCMD, ΔT ≈ 24 °C) over a test period of 6 h. The experimental findings suggest these novel graphene-coated membranes as promising materials to develop functional membranes for high-performing water desalination.

Keywords: antiwetting and antifouling properties; graphene; membrane distillation; multi-scale roughness.

Grants and funding

This research was funded by the grant from ‘the Italian Ministry of Foreign Affairs and International Cooperation’ within the framework of the Great Relevance International Project Italy (MAECI)-China (NSFC) 2018–2020—New Materials, with particular reference to Two-dimensional systems and Graphene (2DMEMPUR), MAE0088962, 21 May 2018.