Fabrication of a Novel (PVDF/MWCNT/Polypyrrole) Antifouling High Flux Ultrafiltration Membrane for Crude Oil Wastewater Treatment

Abstract

The present work deals with the fabrication of novel poly(vinylidene fluoride) (PVDF)/Multi-wall Carbon Nanotubes (MWCNT)/Polypyrrole (PPy) ultrafiltration membrane by phase inversion technique for the removal of crude oil from refinery wastewater. In situ polymerization of pyrrole with different concentrations of MWCNT ranging from 0.025 wt.% to 0.3 wt.% in PVDF prepared solutions. Measurement of permeability, porosity, contact angle, tensile strength, zeta potential, rejection studies and morphological characterization by scanning electron microscopy (SEM) were conducted. The results showed that membrane with (0.05% MWCNT) concentration had the highest permeability flux (850 LMH/bar), about 17 folds improvement of permeability compared to pristine PVDF membrane. Moreover, membrane rejection of crude oil reached about 99.9%. The excellent performance of this nanocomposite membrane suggests that novel PVDF modification with polypyrrole had a considerable effect on permeability with high potential for use in the treatment of oily wastewater in the refinery industry.

Outstanding Separation Performance of Oil-in-Water Emulsions with TiO2/CNT Nanocomposite-Modified PVDF Membranes

“…It could also help the formation of the oily cake layer on the surface, slowing the filtration more intensely. These observations are in line with the findings of Hudaib et al [ 40 ], who also reported reduced water permeability and lower flux (during the filtration of oil emulsions) above a specific CNT concentration (>0.05–0.1 wt. % CNT content in their PVDF/MWCNT/polypyrrole mixed matrix membranes).…”

“…After reaching a VRR of 2, the concentrated oily contaminants attached intensely onto the surface, resulting in high reversible and total filtration resistances ( Figure 4 ), and ultimately a slightly lower flux than the flux measured for the membrane with a pure TiO 2 coating ( Figure 2 ). Regarding this, the recent findings of Hudaib et al [ 40 ] can be mentioned again, who reported decreasing total filtration resistances for PVDF/MWCNT/polypyrrole membranes with 0.0025%, 0.05%, and 0.1% CNT contents during the filtration of synthesized refinery wastewater, but at a 0.3% CNT content, a higher total filtration resistance was observed. Thus, in the mentioned study, the 0.1% CNT content was the optimal value, but the membranes did not contain TiO 2 , and the flux did not exceed 100 L/m 2 h during the filtration of the emulsion.…”

“…Comparing the values of the commercial and TiO 2 /CNT 2% -coated membranes, 4–7 times higher fluxes (510, 900, and 1340 L/m 2 h) were achieved with the modified membranes, depending on the applied transmembrane pressure (0.1, 0.2, and 0.3 MPa, respectively). To emphasize the importance of this beneficial property, we compared the results with another recent study [ 40 ], in which oil emulsions were filtered with PVDF−MWCNT membranes at four different transmembrane pressures of 0.1, 0.2, 0.3, and 0.4 MPa. The fluxes were between ~380 and 665 L/m 2 h at a 0.1 MPa transmembrane pressure, depending on the amount and the surface nature of the used MWCNTs.…”

Photocatalytic Self-Cleaning PVDF Membrane Blended with MWCNT-ZnO Nanocomposites for RhB Removal

“…Polyvinylidene fluoride (PVDF) membranes are universally used due to their good mechanical strength, high dielectric constant, and thermal stability [7]. As in the case of other polymer membranes, the use of PVDF membranes to filtration is restricted by membrane fouling, which occurs both on the surface and inside the pores and is a consequence of its hydrophobic property.…”