780 publications from this institution
No abstract is provided for this article.
A two-dimensional zeolitic imidazolate framework with a leaf-like structure (ZIF-L) was synthesized in aqueous solution at room temperature with a molar ratio of Zn+2/Hmim (1: 8). Various triethylamine (TEA) concentrations were also used for the rapid production of ZIF-L. Different characterization techniques like X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA) were performed to investigate the effect of base type additive triethylamine (TEA) on the crystal morphology, crystallinity, particle size and thermal stability of ZIF-L particles. From the experimental results, it was found that ZIF-L with a particle size of 5.3 μm was formed at TEA/total mole ratio of 0, but particle size was decreased when TEA/total mole ratio was increased up to 0.0003. The smallest ZIF-L particles obtained were 3 μm that showed excellent thermal stability. It can be concluded that this promising synthesis method with base-type additive would provide the new insights in the development of ZIFs materials in economical ways. © 2018, Malaysian Society of Analytical Sciences.
This chapter presents the development of membranes and membrane processes. The first part of this chapter addresses the fundamental principle of the membrane, including the definition of a membrane and its performance parameters, i.e., flux and selectivity. The membrane processes are influenced by their classifications, i.e., membrane's material type, separation regime, and membrane geometry. The examples of membrane processes according to a driving force such as transmembrane pressure (microfiltration, ultrafiltration, nanofiltration, reverse osmosis), concentration gradient (forward osmosis), and vapor partial pressure gradient (gas separation, membrane distillation) are included. The chapter ends with a discussion on the fouling issues in membrane applications.
Water purification from various sources is crucial in mitigating global water shortage and ensuring universal access to clean and safe drinking water. Incorporation of nanoparticles, such as titania (TiO2) or zirconia (ZrO2) into/onto ceramic membranes (nanocomposite ceramic membranes) is a promising modified version of conventional ceramic membranes and has emerged as a highly viable solution for enhancing water purification processes due to their outstanding properties in improving membrane properties compared to conventional ceramic membranes. However, nanocomposite ceramic membranes encounter significant obstacles, including poor dispersion of nanoparticles within the membrane matrix, the potential for nanoparticle leaching during the purification process, and the accumulation of fouling agents. Despite the limited number of reviews on nanocomposite ceramic membranes in water purification applications, the uniqueness of this review is addressing these limitations and examines recent technical solutions, developments, and strategies to overcome these challenges and enhance their performance. By effectively addressing these limitations through improved nanoparticle dispersion and attachment in the membrane matrix and enhanced fouling resistance properties, cutting-edge strategies can be developed to optimize nanocomposite ceramic membranes and significantly improve their performance across various water purification applications. This review also discusses the research outlook of incorporating nanomaterials with ceramic membranes, modification techniques and the effect of nanomaterials on ceramic membrane properties. Although recent advancements in nanocomposite ceramic membranes for water purification, significant limitations persist. Therefore, this review also highlights the future research direction to enhance the properties and performance of nanocomposite ceramic membranes in water purification applications.
No abstract is provided for this article.
A photocatalytic reactor based on novel dual-layer hollow fibre membranes with immobilized titanium dioxide (TiO2) nanoparticles was proposed in this study and tested for the degradation of highly recalcitrant endocrine disrupting compound of nonylphenol (NP). The presence of TiO2 on the outer surface of dual-layer hollow fibres was confirmed by scanning electron microscopy (SEM), energy dispersion of X-ray (EDAX), and atomic force microscopy (AFM). The effect of TiO2 loading, where the mass fraction TiO2/PVDF was varied from 0 to 1, on the degradation of toxic NP was evaluated by high-performance liquid chromatography (HPLC). The addition of TiO2 nanoparticles showed a significant effect on the membrane pore size and NP degradation rate. The presence of TiO2 on the outer layer of dual-layer hollow fibre membranes actively functioned as a photocatalyst, with the hollow fibre of TiO2/PVDF ratio of 1 possessed the highest NP degradation rate.
Water scarcity at global level has called for attentions to establish new and innovative technologies that can be tapped to provide sustainable solutions to water crisis. Membrane-based desalination has been acknowledged as one of the promising approaches to resolve the global challenges. Currently, different membrane-based technologies have been deployed worldwide for clean water production. However, despite the great advances made in terms of the permeate flux and rejection, the practical application of membrane for desalination is still limited by the inevitable membrane fouling issue. Membrane fouling is known to be the major culprit to the elevated operating costs due to the deterioration of permeate flux, increasing transmembrane pressure, and frequent chemical cleaning which shorten the membrane's lifespan. This review provides insights into the recent advancement in mitigating membrane desalination fouling. The fouling control strategies which encompass the efforts made in the novel membrane development, feed water pretreatment, and membrane cleaning are highlighted. The advantages and limitations of these techniques are discussed and reviewed based on a substantial number of up-to-date literatures.
Hemodialysis is the prevailing approach in renal replacement therapy, critically required for eliminating uremic toxins from the blood of individuals suffering from end-stage renal disease (ESRD), but its efficacy is hindered by membrane biocompatibility and inadequate removal of uremic toxins. Blood-membrane interactions during HD trigger immune responses, impacting thrombogenesis, complement activation, leukocyte activation, coagulation, cytokine production, and oxygen radical generation. Despite research progress, membrane biocompatibility remains a global concern due to potential harm, morbidity, and mortality. This article reviews dialysis fundamentals, encompassing historical context, the evolution of configurations and materials, commercially available membranes, challenges, and recent advancements in HD membranes furthermore this review highlights the impacting clinical studies conducted for hemodailysis advancement. It emphasizes the critical need for improved hemocompatibility, discussing recent research and techniques like surface modifications and coating. These approaches aim to minimize platelet activation, coagulation, and enhance membrane performance, showcasing promising potential for future improvements in dialysis outcomes and patient comfort.
Endocrine disrupting compound (EDC) namely bisphenol A (BPA) is toxic and has capability to give adverse effect towards health. The outflow of BPA into water bodies raised concern and suitable water treatment is needed. Photocatalysis is promising method nowadays to move towards green technology. The combination of copper (II) oxide-vanadium tetrasulfide (CuO-VS4) incorporated with polyvinylidene fluoride (PVDF) membrane as photocatalytic dual layer hollow fibre membrane (DLHF) was chosen in this study as novel energy storage photocatalytic membrane towards efficient degradation of BPA under visible light illumination. CuO and CuO-VS4 was synthesized via sol-gel and hydrothermal method respectively at different drying temperature and hydrothermal time. PVDF/CuO-VS4 DLHF photocatalytic membrane was fabricated using co-extrusion method by varying the ratio of CuO-VS4 and characterized for the morphology and properties as well photocatalytic test by collecting the sample from photoreactor. CuO synthesized at room temperature while CuO-VS4 synthesized at 12 hours hydrothermal time was chosen to be depositing into PVDF membrane matrix. The 0.25 PVDF/CuO-VS4 DLHF exhibit the largest pore size and uniform distribution of CuO-VS4 while photocatalytic activity achieved 70.19% and 73.24% of photodegradation and removal of BPA respectively. Around 53.09% of BPA successfully degraded after 120 min of analysis in dark condition for efficient energy storage capability. A novel PVDF/CuO-VS4 DLHF can act as preferential photocatalytic membrane for BPA removal and as potential energy storage material for wastewater treatment.
