The Influence of Nanomagnetite Filler (Fe3O4) and Magnetic Induction on the Characteristics and Performance of PVDF/SWCNT Composite Membrane
Sifathul Jannah (a), Fitri Khoerunnisa (a*), Hendrawan Hendrawan (a), Mita Nurhayati (b), Eli Hendrik Sanjaya (c), Wijayanti Dwi Astuti (4)

a) Department of Chemistry, Universitas Pendidikan Bandung 40154, Indonesia
* fitri[at]upi.edu
b) Department of Advanced Science and Technology Convergence, Kyungpook National University, 2559 Gyeongsang-daero, Sangju-si 37224, South Korea
c) Department of Chemistry, Universitas Negeri Malang, Malang, 90222, Indonesia
d) Department of Electrical Engineering and Informatics, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia

Abstract

The utilization of nanofiltration technology in the endeavor to harness seawater as an alternative source of clean water holds significant importance for development. Nanofiltration is used during the pretreatment phase of desalination, as an effort to curtail energy consumption and costs. The objective study is to investigate the influence of Fe3O4 nanomagnetite filler and magnetic induction on the characteristics and performance of the PVDF/SWCNT composite membrane. The composite membrane is synthesized through the phase inversion method with an optimal composition of PVDF casting solution (18 g), SWCNT (1 mg), and Fe3O4 (4 mg) in DMAc solvent. Magnetic induction is executed using a 1 Tesla magnet for a duration of 30 seconds after the casting solution is deposited onto the glass plate. The composite membrane is characterized by employing FTIR, XRD, SEM, hydrophilicity testing, and porosity analysis. The performance tests include pure water flux, dye rejection, and zero point of charge measurements. The results demonstrate that the addition of nanomagnetite filler and magnetic induction can enhance hydrophilicity (θ 70 to 50.96), porosity (48% to 73.07%), the changes in structure and morphology indicated by the interaction between Fe3O4 and PVDF/SWCNT, crystal size enhancement, d-spacing reduction, and alteration in lattice structure within the PVDF matrix that can lead to the enhancement of membrane performances. The addition of nanomagnetite filler and magnetic induction enhances the performance of the PVDF/SWCNT membrane. as evidenced by the increased pure water flux (6.54 L/m^2.h to 151.79 L/m^2.h) and the rejection of Rhodamine B and Methyl Orange up to 90%. Based on the zero point of charge measurement, it can be predicted that the membrane rejection mechanism occurs through size exclusion and electrostatic interactions.

Keywords: Composite membrane, nanomagnetite, magnet induction, PVDF/SWCNT

Topic: Chemistry