مشروع البحث: OMNIPHOBIC SILICA SAND CERAMIC HOLLOW FIBER- BASED MEMBRANE DISTILLATION FOR DESALINATION
| dc.contributor.advisor | جامعة الماليزية | |
| dc.date.accessioned | 2024-12-12T13:05:33Z | |
| dc.date.available | 2024-12-12T13:05:33Z | |
| dc.description | pertama kajian, serbuk pasir silika dicirikan menggunakan teknik pencirian yang berbeza. Seterusnya, SCHFM telah dihasilkan melalui gabungan teknik penyongsangan fasa/pembakaran, dan morfologi serta kekuatan mekanikal SCHFM diuji menggunakan SEM, mikroskop daya atom, dan ujian lenturan tiga titik. Kesan dua parameter proses penghasilan iaitu suhu pembakaran (1300 °C hingga 1450 °C) dan kandungan seramik (50 wt% hingga 57.5 wt%) terhadap kekuatan mekanikal, morfologi dan ketelapan air tulen SCHFM telah ditentukan. Hasilnya, suhu pembakaran yang paling sesuai ialah 1300 °C. Struktur morfologi seperti span dan liang jari serta kekuatan mekanikal 78.5 MPa pada muatan serbuk seramik 55 wt% adalah yang terbaik bagi SCHFM yang dihasilkan. Seterusnya, kajian, kesan kedudukan lapisan FAS juga ditentukan untuk pengurangan fenomena pembasahan dan pengenapan dalam penyulingan membran sentuhan langsung (DCMD) melalui satu siri langkah iaitu 1) pemendapan nanopartikel silika sfera (SiNPs), 2) pengflourinan oleh FAS17 dan 3) PVDF-HFP untuk pelekatan SiNPs ke atas permukaan SCHFM. Pada awalnya, SCHFM adalah bersifat hidrofilik, tetapi gentian geronggang bertukar kepada omnifobik serta menunjukkan sudut sentuhan yang tinggi bagi semua cecair seperti air suling, minyak sawit dan etanol. Sebagai contoh, salah satu membran yang diubah suai dikenali sebagai SiNPs-FAS-PVDF/FAS, adalah bersifat superomnifobik ke atas air (167°) dan minyak sawit (157°), serta hampir superomnifobik ke atas etanol (146.1°). Eksperimen DCMD dengan larutan suapan 35 g / L NaCl dan 10 mg / L asid humik telah dijalankan dengan dua membran yang dikenali sebagai SiNPs-FAS-PVDF / FAS. Hasil menunjukkan rintangan anti-enapan dan anti-pembasahan yang tinggi selama 100 jam tempoh operasi DCMD tanpa pengurangan nilai fluks membran serta penyingkiran garam yang stabil. Keputusan ini | |
| dc.description.abstract | ABSTRACT Ceramic membranes are well-known to have unique characteristics, including thermal, chemical and mechanical stabilities. The main drawback of ceramic membranes that limits their commercialisation is their high cost of raw materials. Also, fouling and wetting are still a major challenge, especially in membrane distillation. To overcome these disadvantages, omniphobic silica sand hollow fibre ceramic membrane (SCHFM) was successfully fabricated via phase inversion/sintering technique using a natural raw material (silica sand). Silica sand is an alternative ceramic material from natural resources. It has a high silica purity of up to 99 %. Additionally, silica sand has various attributes that makes it ideal for water filtration; such attributes include high acidic chemical resistance and high hardness. These attributes enhance the mechanical strength of silica sand. In the first stage of the study, silica sand powder was chemically and physically characterised using different characterization techniques. Subsequently, the SCHFMs were fabricated through phase inversion/sintering technique, the morphology and mechanical strength of SCHFMs were investigated using SEM, atomic force microscopy, and three-point bending test, respectively. The effects of two major fabrication process parameters; i.e., sintering temperature (1300 to 1450 °C) and ceramic content (50 to 57.5 wt%) on the mechanical strength, morphology and pure water flux of the SCHFM were examined. Based on the findings, the most suitable sintering temperature was 1300 °C. Satisfactory morphological structure of sponge- and finger-like voids and mechanical strength of 78.5 MPa at 55 wt% ceramic powder loading were found to be advantageous for the characteristics of the fabricated SCHFM. In the second stage of the study, surface functionalization of the laboratory spun SCHFM was performed, the effect of the FAS layer position was investigated for the reduction of the wetting and fouling in DCMD following a series of steps 1) deposition of spherical silica nanoparticles (SiNPs), 2) FAS17 and 3) PVDF-HFP coating to glue SiNPs to the SCHFM surface. Initially, the pristine SCHFM was hydrophilic, but when the surface modification was fully applied, the hollow fiber became omniphobic, exhibiting high contact angles for all tested liquids of different surface tensions, such as distilled water, palm oil and ethanol. For example, one of the modified hollow fibers, called SiNPs FAS-PVDF/FAS, was superomniphobic toward water (167°) and palm oil (157°), and near superomniphobic toward ethanol (146.1°). As for the DCMD experiments with the feed solution containing 35 g/L NaCl and 10 mg/L humic acid conducted in the third stage of the study, two of the modified hollow fibers called SiNPs-FAS PVDF/FAS showed high antifouling and anti-wetting resistance during the entire DCMD operation period of 100 h with no observable flux reduction and stable salt rejection. The anti-fouling resistance of this hollow fiber was further evidenced by the cleanness of the surface in the micrographic image taken after the long-term DCMD run, SEM, contact angle, as well as energy dispersive X-ray analysis. The omniphobicity of this hollow fiber is ascribed to the combined effects of surface tension decrease by the FAS17 fluorination and the formation of the re-entrant structure by the densely packed SiNPs. With reasonably high fluxes of 46.58 kg/m2.h SiNPs-FAS-PVDF/FAS, and 100% of salt rejection, omniphobic hollow fibre ceramic membranes (SiNPs-FAS-PVDF/FAS) have potential for seawater desalination by DCMD. | |
| dc.identifier | 358 | |
| dc.identifier.uri | https://dspace.academy.edu.ly/handle/123456789/878 | |
| dc.subject | membran SiNPs-FAS-PVDF/FAS mempunyai potensi untuk proses penyahgaraman air laut melalui kaedah DCMD. | |
| dc.title | OMNIPHOBIC SILICA SAND CERAMIC HOLLOW FIBER- BASED MEMBRANE DISTILLATION FOR DESALINATION | |
| dspace.entity.type | Project | |
| project.endDate | 2023 | |
| project.funder.name | الهندسة الكيميائية والطاقة | |
| project.investigator | SABER ABDULHAMID M ALFTESSI | |
| project.startDate | 2022 |