Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> Nanoparticles
The combination of photocatalysis and membrane filtration in a single reactor has been proposed, since the photocatalytic treatment may degrade the pollutants retained by the membrane and reduce fouling. However, polymeric membranes can be susceptible to degradation by UV radiation and free radicals...
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| Format: | Article |
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MDPI AG
2021-12-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/14/1/124 |
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| author | Geórgia Labuto Sandra Sanches João G. Crespo Vanessa J. Pereira Rosa M. Huertas |
| author_facet | Geórgia Labuto Sandra Sanches João G. Crespo Vanessa J. Pereira Rosa M. Huertas |
| author_sort | Geórgia Labuto |
| collection | DOAJ |
| description | The combination of photocatalysis and membrane filtration in a single reactor has been proposed, since the photocatalytic treatment may degrade the pollutants retained by the membrane and reduce fouling. However, polymeric membranes can be susceptible to degradation by UV radiation and free radicals. In the present study, five commercial polymeric membranes were exposed to ultraviolet (UV) radiation before and after applying a sol–gel coating with TiO<sub>2</sub> nanoparticles. Membrane stability was characterized by changes in hydrophilicity as well as analysis of soluble substances and nanoparticles detached into the aqueous medium, and by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometry (EDS) for structural, morphological, and elemental distribution analysis, respectively. The TiO<sub>2</sub> coating conferred photocatalytic properties to the membranes and protected them during 6 h of UV radiation exposures, reducing or eliminating chemical and morphological changes, and in some cases, improving their mechanical resistance. A selected commercial nanofiltration membrane was coated with TiO<sub>2</sub> and used in a hybrid reactor with a low-pressure UV lamp, promoting photocatalysis coupled with cross-flow filtration in order to remove 17α-ethinylestradiol spiked into an aqueous matrix, achieving an efficiency close to 100% after 180 min of combined filtration and photocatalysis, and almost 80% after 90 min. |
| first_indexed | 2024-03-10T03:25:12Z |
| format | Article |
| id | doaj.art-8e35bfa9d26e4f6886bf05803fef515d |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-03-10T03:25:12Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-8e35bfa9d26e4f6886bf05803fef515d2023-11-23T12:10:13ZengMDPI AGPolymers2073-43602021-12-0114112410.3390/polym14010124Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> NanoparticlesGeórgia Labuto0Sandra Sanches1João G. Crespo2Vanessa J. Pereira3Rosa M. Huertas4Department of Chemistry, Universidade Federal de São Paulo, Diadema 09913-030, BraziliBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, PortugalLAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, FCT NOVA, Universidade NOVA de Lisboa, 2829-516 Caparica, PortugaliBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, PortugaliBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, PortugalThe combination of photocatalysis and membrane filtration in a single reactor has been proposed, since the photocatalytic treatment may degrade the pollutants retained by the membrane and reduce fouling. However, polymeric membranes can be susceptible to degradation by UV radiation and free radicals. In the present study, five commercial polymeric membranes were exposed to ultraviolet (UV) radiation before and after applying a sol–gel coating with TiO<sub>2</sub> nanoparticles. Membrane stability was characterized by changes in hydrophilicity as well as analysis of soluble substances and nanoparticles detached into the aqueous medium, and by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometry (EDS) for structural, morphological, and elemental distribution analysis, respectively. The TiO<sub>2</sub> coating conferred photocatalytic properties to the membranes and protected them during 6 h of UV radiation exposures, reducing or eliminating chemical and morphological changes, and in some cases, improving their mechanical resistance. A selected commercial nanofiltration membrane was coated with TiO<sub>2</sub> and used in a hybrid reactor with a low-pressure UV lamp, promoting photocatalysis coupled with cross-flow filtration in order to remove 17α-ethinylestradiol spiked into an aqueous matrix, achieving an efficiency close to 100% after 180 min of combined filtration and photocatalysis, and almost 80% after 90 min.https://www.mdpi.com/2073-4360/14/1/124membrane stabilityUV photodegradationTiO<sub>2</sub> coatinghybrid reactorhormone removal |
| spellingShingle | Geórgia Labuto Sandra Sanches João G. Crespo Vanessa J. Pereira Rosa M. Huertas Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> Nanoparticles Polymers membrane stability UV photodegradation TiO<sub>2</sub> coating hybrid reactor hormone removal |
| title | Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> Nanoparticles |
| title_full | Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> Nanoparticles |
| title_fullStr | Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> Nanoparticles |
| title_full_unstemmed | Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> Nanoparticles |
| title_short | Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO<sub>2</sub> Nanoparticles |
| title_sort | stability of polymeric membranes to uv exposure before and after coating with tio sub 2 sub nanoparticles |
| topic | membrane stability UV photodegradation TiO<sub>2</sub> coating hybrid reactor hormone removal |
| url | https://www.mdpi.com/2073-4360/14/1/124 |
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