Publications

Wetland water is opted as the source of domestic water supply when the availability of clean fresh water is scarce. Wetland water requires proper treatment due to the high concentration of organic matter and high salinity, particularly in the dry season. This research aims to synthesize, characterize, and investigate the performance of polyvinylidene fluoride (PVDF)-TiO2 hollow fiber membrane for wetland saline water desalination via pervaporation. The PVDF-TiO2 hollow fiber membranes were fabricated through the dry wet spinning method under various air gaps (10, 15, and 20 cm). Then, the resulting membranes were tested in a pervaporation process at temperatures of 25, 40, and 60°C. Results show that the incorporation of TiO2 into the PVDF matrix imparted hydrophilicity properties into the resultant membranes. The presence of TiO2 was confirmed by the TiO2 stretching vibration at 1640 cm-1 (FTIR) and the TiO2 phase at diffraction peaks at 25.5 and 37°. The membranes exhibited the highest water flux (7.48 kg/m2.h) and salt rejection ( 99.5%) at 40°C. Overall, the developed PVDF-TiO2 hollow fiber membranes showed encouraging results and demonstrated their effectiveness for the desalination of wetland saline water.

In an effort to further improvement of LSCF hollow fiber membrane properties in oxygen purification applications, this work studied the use of polyethylene glycol (PEG) with a different molecular weights of 2000, 3400 and 6000 Da as a pore former. A well-prepared hollow fiber membrane was successfully fabricated via extrusion followed by a sintering method. The results showed that the addition of PEG increased the viscosity of the dope suspension and formed a constant asymmetric pore configuration of the membrane after sintering at 1250 °C. The increasing molecular weight of PEG also leads to a decrease in the mechanical strength of the membranes, indicating that finger-like pores were sacrificed by forming irregular pores. The gas tightness was also examined under room temperature which showed that membrane with PEG 3400 achieved the best tightness with the nitrogen permeability of 3.55 × 10−5 mol·m−2·s−1·Pa−1. The oxygen permeation of the membranes was also influenced by the addition of PEG, where the highest oxygen permeation flux of 6.07 × 10−8 mol·cm−2·s−1 was obtained using a hollow fiber membrane with PEG 3400 due to the existence of the lowest dense layer thickness.

This study aims to develop a new PEM for fuel cell applications consisting of PSU/SPEKEKK/SGO membrane with improved physiochemical properties to surmount the low power generation of Nafion. The DFT calculations using NCI plots show that there are network interactions between PSU and SPEKEKK, established by the hydrogen bonding and vdW interactions. SGO was incorporated into the as-prepared PSU/SPEKEKK membrane. A solution casting method was employed to fabricate SGO-loaded composite membranes in the range of 0.1% to 1.5% (wt. %). Structural evidence of the SGO and composite membranes was characterized by ATR-FTIR and FESEM, respectively. Adding SGO to PSU/SPEKEKK shows a significant increase in proton conductivity due to the presence of more protonated sites (SO3H) and water-mediated interactions for proton conduction. Of all the compositions considered, PSU/SPEKEKK/SGO-0.6-1.5% loading was found to have the highest proton conductivity, 0.03Scm-1. Although adding SGO to the composite membrane has reduced water absorption, the hydrophilic oxygenated functional groups in SGO, the bound water molecules, and the increased –SO3H groups have successfully improved the proton conductivity. The findings reveal that all composite membranes showed excellent oxidative stabilities for 32 hours in Fenton’s reagent. To summarize, all composite membranes fabricated in this study showed acceptable water uptake and swelling ratio, high oxidation, excellent thermal stability, and high proton conductivity.

The generation of microplastics (MPs) has increased recently and become an emerging issue globally. Due to their long-term durability and capability of traveling between different habitats in air, water, and soil, MPs presence in freshwater ecosystem threatens the environment with respect to its quality, biotic life, and sustainability. Although many previous works have been undertaken on the MPs pollution in the marine system recently, none of the study has covered the scope of MPs pollution in the freshwater. To consolidate scattered knowledge in the literature body into one place, this work identifies the sources, fate, occurrence, transport pathways, and distribution of MPs pollution in the aquatic system with respect to their impacts on biotic life, degradation, and detection techniques. This article also discusses the environmental implications of MPs pollution in the freshwater ecosystems. Certain techniques for identifying MPs and their limitations in applications are presented. Through a literature survey of over 276 published articles (2000–2023), this study presents an overview of solutions to the MP pollution, while identifying research gaps in the body of knowledge for further work. It is conclusive from this review that the MPs exist in the freshwater due to an improper littering of plastic waste and its degradation into smaller particles. Approximately 15–51 trillion MP particles have accumulated in the oceans with their weight ranging between 93,000 and 236,000 metric ton (Mt), while about 19–23 Mt of plastic waste was released into rivers in 2016, which was projected to increase up to 53 Mt by 2030. A subsequent degradation of MPs in the aquatic environment results in the generation of NPs with size ranging from 1 to 1000 nm. It is expected that this work facilitates stakeholders to understand the multi-aspects of MPs pollution in the freshwater and recommends policy actions to implement sustainable solutions to this environmental problem.

It is shown that a simple photometric method provides high accurate result for the wavelength at which the retardance of a phase plate assumes the value π/2. Result for a quartz quarterwave plate is presented and is found to be in high agreement with the result obtained by the modified Senarmont arrangement for simultaneous retardance measurement of two phase plates.

Suitable membranes for blood‐contacting medical applications need to be resistant in confrontation with blood proteins and cells, while possessing high blood compatibility and permeability at the same time. Herein, an overview of the recent advances and strategies that have been used to enhance the hemocompatibility of polymeric membranes is provided. The review focuses on two modification strategies: (i) physical modifications and (ii) chemical modifications. It also highlights the current progress in the design of hemocompatible‐functionalized membranes for biomedical applications. Subsequently, the commonly applied biocompatibility tests are also discussed and finally the future perspectives of the application of polymeric membranes in the biomedical field are presented. image

Islam Liberal merupakan satu aliran pemikiran yang menghendaki kepada keterbukaan dalam berijtihad yang melampaui batas-batas agama yang telah sedia ada sepertimana di dalam al-Quran dan al-Sunnah. Artikel ini bertujuan untuk membincangkan pendekatan pengajian Islam di Malaysia khususnya di peringkat IPTA dalam menangani ancaman Islam Liberal tersebut. Kajian ini menggunakan pendekatan kajian kepustakaan dan analisis dokumen yang dibahagikan kepada empat bahagian. Pertama, pengenalan mengenai kajian. Kedua, huraian mengenai Islam Liberal yang merangkumi sejarah perkembangannya serta ciri-ciri pemikiran gagasan Islam Liberal tersebut. Ketiga, perbincangan mengenai kronologi dan perkembangan Pengajian Islam di Malaysia. Keempat, pendekatan Pengajian Islam dan yang kelima, perbincangan mengenai Pengajian Islam dalam mendepani ancaman Islam Liberal. Dapatan awal artikel ini merumuskan bahawa Pengajian Islam di Malaysia melalui subjek-subjek yang ditawarkan dilihat berupaya menjadi satu sistem pendidikan yang kompetitif, memenuhi tuntutan semasa dalam menghadapi cabaran globalisasi seperti cabaran pemikiran Islam Liberal yang wujud pada hari ini.

A novel thermally modified non-solvent induced phase separation (T-NIPS) fabrication method to produce translucent hollow fiber PVDF (THF-PVDF) photocatalytic membrane is developed. This method relies on attacking polymer crystalline property of PVDF by two steps temperature treatment process involving melting at high temperature (200°C) and rapid cooling at 0°C during spinning process thereby producing more γ-phase crystalline structure PVDF. The effect of membrane translucency on the photodegradation efficiency of immobilized photocatalyst were assessed. Graphitic carbon nitride in modified morphological structure (hollow nanofiber) were utilized. Membrane’s rejection, pure water flux and permeate flux of oil produced water were also investigated. The overall data shows that the produced membrane exhibits high translucency between 60.0% and 93.9% with THF-PVDF/PVP-GCN (2.0) exhibiting the highest. Comparatively, the filtration experiment on membrane with GCN photocatalyst showed high pure water flux (1200 L/m2h) and rejection (90%) of OPW than bare THF-PVDF and THF-PVDF/PVP. The photodegradation of GCN in suspended mode showed 99.98% degradation. The efficiency of GCN when immobilized in translucent membrane showed 95% photodegradation while membrane that is produced following commercial NIPS method showed only 49.40% photodegradation of OPW. This excellent performance is attributed by the transparency of membrane where the penetration of light is fully accommodated to the produced translucent photocatalytic membrane. The translucent photocatalytic membrane's preparation process and exceptional degradation efficiency meet the demands of current industrial productivity while also offering a bright application prospect for the industry.

Dye hurts the threat of human health problems and environmental pollution. Microcrystalline cellulose (MCC) based membrane is a good material to be used as an dye separation membrane for having the high hydrophilicity of the membrane. It has been successfully isolated from kapok (ceiba pentandra) with characteristic X-ray diffraction patterns and FTIR absorption peaks, which corresponded to the typical peaks of cellulose. The ultrafiltration membrane was made up of a cellulose acetate matrix created using the phase inversion method. Characterization results indicated that the inclusion of MCC derived from kapok led to a reduction in the contact angle from 65 to 52o, and an increase in membrane porosity from 82 to 85%. In the separation of dye, the composite membrane incorporating MCC filler demonstrated superior performance compared to the membrane lacking MCC, manifesting in an elevated water flux from 43 to 84 L/m².h and methylene blue (MB) rejection from 64 to 99%. The use of MCC as a filler in cellulose acetate membranes can enhance the characteristics and performance of the membrane in MB separation.

Membrane filtration exhibits excellent separation performance for water and wastewater treatment but is still limited by the membrane fouling. This study presents a novel membrane rotating biological contactor (MRBC) that combines a conventional rotating biological contactor (RBC) with membrane filtration. MRBC combines conventional RBC with the membrane filtration placed in between two adjacent rotating disks to offer inherent control over membrane fouling. The disks rotations provide some degree of foulant removal, maintain membrane permeability, and potentially save a substantial amount of energy. The biological and hydraulic performance of MRBC was compared with a series of RBC and external membrane filtration (RBC + ME) where the membrane is treated as a post-treatment unit. Results show that the MRBC enhances not only the biological performance but also offers advantages for inherent membrane fouling control through the rotation of the disk. Membrane fouling control primarily originates from the enhanced shear rate from higher disk rotation and minimum membrane-to-disk gap. The hydraulic performance is 92.4% higher than literature, which further enhanced at smaller membrane-to-disk gaps and higher disk rotations. The highest steady-state permeability of 297 L/(m2.h.bar) and 288 L/(m2.h.bar) results at 40 rpm disk rotational speed and 0.5 cm membrane-to-disk gap, respectively. A projected full-scale MRBC consumes 0.18 kWh/m3 permeate, one-fourth of the energy for the referenced MBR system thanks to the active role of disks rotation for membrane fouling control which eliminates the need of extensive aeration like in the traditional MBRs. MRBC offers a promising alternative for traditional wastewater treatment as a low energy foot-print process, which is in line with the requirements of sustainable development and promotes the development of cleaner production.