Publication: Polyvinylidene fluoride/calcium carbonate membranes with the nonwetted and wetted surface for dual-phase separation
| datacite.subject.fos | oecd::Engineering and technology::Chemical engineering | |
| dc.contributor.author | Sarah Qistina binti Zaliman | |
| dc.date.accessioned | 2025-11-28T04:09:13Z | |
| dc.date.available | 2025-11-28T04:09:13Z | |
| dc.date.issued | 2024-09 | |
| dc.description.abstract | Dual-phase separation using membranes involves the permeation of target compounds between gas-liquid and liquid-liquid phases. However, the permeation can be restricted by surface wetting important. In this work, poly(vinylidene fluoride) (PVDF) membranes with switchable surface wetting were developed through nanoparticle incorporation and 3D-imprinting, followed by drying or wetting after phase inversion. In order to achieve the nanoroughness, low cost and biocompatible calcium carbonate (CaCO3) nanoparticles were introduced into PVDF dope solution. A micro-roughness was imprinted on the membrane by phase inversion in a water bath after casting on a woven support. For nanotemplating, the nanoparticles were premodified using stearic acid to reduce surface energy or removed using ethylenediaminetetraacetic acid. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to observe the presence of CaCO3 nanoparticles. As a result of the addition of CaCO3 and stearic acid-modified CaCO3 (SA-CaCO3), the membrane pore size and porosity were significantly improved due to demixing during phase inversion. Removing CaCO3 nanoparticles using ethylenediaminetetraacetic acid enlarged the pore size greatly. PVDF/CaCO3 and PVDF/SA- CaCO3 membranes attained superhydrophobic surface after drying. Working as the membrane gas contactor, the PVDF membrane incorporated with SA-CaCO3 reached a high CO2 permeation flux of 1.86 ±0.05×10-2 mol m-2 s-1 and slight changes in surface hydrophobicity after 50 h of being immersed in amine solution. On the other hand, the hydrophobic PVDF and PVDF/SA-CaCO3 membranes developed in this work were rinsed with absolute ethanol and immersed in distilled water to attain a wetted surface. The non-wetted and wetted membranes were then tested in the separation of oil in water (O/W) and water in oil emulsion (W/O), respectively. A dead-end filtration setup was used to examine their separation efficiency for the liquid-liquid phase under the operating pressure of 0.2 bar (O/W) or 1 bar (W/O). The oil (O/W) could be separated effectively without significant fouling due to the formation of an underwater oleophobic surface. However, the removal of water (W/O) was considerably inefficient slow due to the large pore size. | |
| dc.identifier.uri | https://erepo.usm.my/handle/123456789/23290 | |
| dc.language.iso | en | |
| dc.title | Polyvinylidene fluoride/calcium carbonate membranes with the nonwetted and wetted surface for dual-phase separation | |
| dc.type | Resource Types::text::thesis::master thesis | |
| dspace.entity.type | Publication | |
| oairecerif.author.affiliation | Universiti Sains Malaysia |