ABSTRACT
A novel modification technique employing a layer-by-layer (LbL) self-assembly method, integrated with a pressure-assisted filtration system, was developed for enhancing a commercial polyethersulfone (PES) microfiltration (MF) membrane. This modification involved the incorporation of tannic acid (TA) in conjunction with graphene oxide (GO) nanosheets. The effectiveness of the LbL method was confirmed through comprehensive characterization analyses, including ATR-FTIR, SEM, water contact angle (WCA), and mean pore size measurements, comparing the modified membrane with the original commercial one. Sixteen variations of PES MF membranes were superficially modified using a three-factorial design, with the deposited amount of TA and GO as key factors. The influence of these factors on the morphology and performance of the membranes was systematically investigated, focusing on parameters such as pure water permeability (PWP), blue corazol (BC) dye removal efficiency, and flux recovery rate (FRR). The membranes produced with the maximum amount of GO (0.1 mg, 0.55 wt%) and TA as the inner and outer layers demonstrated remarkable FRR and significant BC removal, exceeding 80%. Notably, there was no significant difference observed when using either 0.2 (1.11 wt%) or 0.4 mg (2.22 wt%) in the first layer, as indicated by the Tukey mean test. Furthermore, the modified membrane designated as MF/TA0.4GO0.1TA0.4 was evaluated in the filtration of a simulated dye bath wastewater, exhibiting a BC removal efficiency of 49.20% and a salt removal efficiency of 27.74%. In conclusion, the novel PES MF membrane modification proposed in this study effectively enhances the key properties of pressure-driven separation processes.
Acknowledgements
This work was supported by the National Council for Scientific and Technological Development (CNPq) and Higher Education Personnel Improvement Coordination (CAPES) Financing Code 001. AMSV is grateful for financial support provided by CNPq (PQ-2 CA research fellowship #311491/2021-9). MFV is grateful for financial support provided by CNPq (PQ-2 CA research fellowship #303540/2021-4). The authors also thank the Complex of Research Support Center (COMCAP) of the State University of Maringá (UEM) for the characterization analysis. The authors would like to thank the University of Minho (UMinho) for the availability of laboratories and equipment, and also acknowledge project UID/CTM/00264/2020 of the Centre for Textile Science and Technology (2C2 T), funded by national funds through FCT/MCTES.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Authors contributions
All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Rebecca Manesco Paixão, Luiz Henrique Biscaia Ribeiro da Silva, Angélica Marquetotti Salcedo Vieira and Maria Teresa Pessoa de Amorim. The first draft of the manuscript was written by Rebecca Manesco Paixão and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
Competing interests
The authors have no conflicts of interest to declare that are relevant to the content of this article.
Availability of data and materials
All data generated or analyzed during this study are included in this published article.