Deposition of graphene nanoparticles associated with tannic acid in microfiltration membrane for removal of food colouring

ABSTRACT

A modified microfiltration (MF) membrane was prepared by flow-through coating method. First the sulfuric acid solution was vacuum filtered on the polyethersulfone (PES) MF membrane, providing the introduction of a sulfonic acid group to the backbone of PES. Sequentially, the polyethyleneimine solution was vacuum filtered to provide amine groups on the membrane surface. Finally, the graphene oxide solution, functionalized with different masses of tannic acid, was vacuum filtered on the membrane surface, producing the cross-linked modified membranes. These were efficient in the removal of anionic food colouring, achieving high removal rates and low fouling, compared to unmodified membrane. The best membrane in terms of bright blue dye removal was the MF PEI₅GO₁TA₄, capable of removing all the feed solution, and demonstrating its possibility of reuse in five cycles of operation.

GRAPHICAL ABSTRACT

KEYWORDS:

• Flow-through coating
• microfiltration
• cross-linked modified membranes
• bright blue dye removal
• low fouling

Acknowledgement

The authors thank the Higher Education Personnel Improvement Coordination CAPES for financial support.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Rebecca Manesco Paixão http://orcid.org/0000-0001-9531-2389

Luiz Henrique Biscaia Ribeiro da Silva http://orcid.org/0000-0002-4085-6618