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Fulfilling the demand of clean potable water to the general public has long been a challenging task in most developing countries due to various reasons. Large-scale membrane water treatment systems have proven to be successful in many advanced countries in the past two decades. This paves the way for developing countries to study the feasibility and adopt the utilization of membrane technology in water treatment. There are still many challenges to overcome, particularly on the much higher capital and operational cost of membrane technology compared to the conventional water treatment system. This review aims to delve into the progress of membrane technology for water treatment systems, particularly in developing countries. It first concentrates on membrane classification and its application in water treatment, including membrane technology progress for large-scale water treatment systems. Then, the fouling issue and ways to mitigate the fouling will be discussed. The feasibility of membrane technologies in developing countries was then evaluated, followed by a discussion on the challenges and opportunities of the membrane technology implementation. Finally, the current trend of membrane research was highlighted to address future perspectives of the membrane technologies for clean water production.

In this study, the potential of graphene oxide-alginate beads (GO-AB) as an adsorbent for bisphenol A (BPA) removal from aqueous solution was investigated. GO was first prepared via modified Hummers’ techniques and aerogel alginate bead with embedded GO was prepared using an extrusion dripping method, where calcium chloride was utilized as a curing agent. The physicochemical characteristics of GO-AB were investigated using XRD, FTIR, BET, TGA. The results revealed that crystal structure and the surface groups of GO and alginate were retained upon formation of GO-AB. A batch adsorption testing was carried out as a function of pH (3, 7, and 9), contact time (up to 420 mins) and initial concentration of BPA (50 - 200 mg·L-1). The adsorption rate was typically faster at the beginning of the adsorption process and started to level off after 180 mins. AB and GO-AB had better adsorption performances at neutral condition (pH 7) as compared to alkaline and acidic environments owing to repulsive electrostatic interaction between BPA and the adsorbent surface’s charge. The sorption kinetic data was observed fitted to the pseudo-second-order kinetics model (R2>0.98) and obeyed the Freundlich isotherm model adsorption behaviour as compared to Langmuir. However, the RL value of Langmuir model is between 0 to 1, which implies favourable adsorption process. The maximum BPA adsorption capacity for AB and GO-AB was found to be 250.00 and 384.62 mg·g-1, respectively indicating that GO-AB is a promising adsorbent for BPA removal from aqueous solution.

Artificial pancreas (AP) device consists of continuous subcutaneous insulin infusion (CSII)pump, continuous glucose monitoring (CGM) sensor, CGM receiver amd control algorithm which measure and regulate current blood glucose level (BGL) of type 1 diabetes (T1D) patients in automated manner. All components of the AP device are now well-established and readily avaialble in the market; however, its control algorithm is still at infant stage. This sometimes leads to insufficient or excessive amounts of insulin injected into their body causing hyperglycaemia or hypoglycaemia episodes, respectively. Mathematical equations of Hovorka model were widely used in the control algorithm; however, the model had shown somewhat lacking in terms of interaction and interrelation of selected parameters in its glucose-insulin dynamics. An attempt was made by previous workers to modify certain subsytem equations in the Hovorka model involving glucose, plasma insulin and insulin action subsystems by introducing additional parameters which, in turn, resulted in producing so-called improved Hovorka equations. This study aims to develop a computer algorithm in oder to simulate the BGL of T1D patient during their meal intakes using the improved Hovorka equations via MATLAB and model based predictive control (MPC). Resuls showed that different amounts of administered insulin (Ut) namely; 0.0003 U/min and 0.009 U/min were required to maintain the BGL within normal range (4.5 to 6 mmol/L) when the amounts of meals (DG) taken by the patient were at 57g CHO and 86.5g CHO during lunch and dinner times, respectively. However, the BGL was above the normal range, i.e. hyperglycaemia when DG and Ut were at 32g CHO and 0.035 U/min, respectively during breakfast time. In conclusion, this study has proven that the improved Hovorka equations can be used to simulate the meal disturbance effect on BGL for T1D patients.

Tapping into solar energy seems to be a viable and sustainable solution for the ongoing global challenges of water scarcity and clean energy shortage. However, the natural mechanism of solar energy-driven water evaporation is often compromised by low evaporation rate and water and solar absorption spectrum mismatch. Therefore, localized heating on the water vapor-liquid interface by light-absorbing materials, known as photothermal materials, has been proposed. This allows the harvesting of energy from the full solar spectrum and high efficiency of light-to-heat conversion. With the emerging advances of photothermal nanomaterials and the urgent demand for a green transition of water treatment technology, the establishment of a photothermal-driven membrane distillation system has been reinvigorated, as seen by the number of publications recently. The efficiency of light absorption and light-to-heat conversion of photothermal materials are critical factors in determining the membrane performances. This review aims to assess the state-of-the-art photothermal materials, including innovative modifications that have been made. The second part is devoted to the emerging aspects and new directions of using these photothermal materials for the development of photothermal membranes. Lastly, the prospects of photothermal membrane for clean water production in the near future are also discussed.

Separation of oil in water emulsion remains as a critical issue due to the high volume of oily wastewater discharged by industrial processes. Membrane technology has a great industrial interest for this oil–water separation owing to its simple operational process and high separation efficiency. However, the hydrophobicity properties of membrane can aid the membrane fouling phenomenon and shorten the life of membranes. As a result, modification of membranes, particularly on hydrophilicity enhancement, is required to optimise the membrane performances. Over the years, graphene and its derivatives, particularly graphene oxide (GO) have gained great research interest in the field of membrane for water and wastewater treatment due to its ultimate thinness and unique layered structure. These features enhance the permeation fluxes, increase hydrophilic property, improve physicochemical properties and provides rich oxygen-containing groups for further modification, making it excellent for ionic/molecular separation. This review article discusses the recent progress of GO-based membranes through various configurations, i.e., free-standing, supported, and polymer nanocomposite for oil–water separation. The advancements of using GO for membrane morphology alteration, fouling mitigations as well as mechanical strength are discussed. The key issues for the development of high-performance GO membranes and prospects for imminent research are highlighted.