ABSTRACT
Water scarcity is a significant concern, particularly in arid regions, due to the rapid growth in population, industrialization, and climate change. Seawater desalination has emerged as a conventional and reliable solution for obtaining potable water. However, conventional membrane-based seawater desalination has drawbacks, such as high energy consumption resulting from a high-pressure requirement, as well as operational challenges like membrane fouling and high costs. To overcome these limitations, it is crucial to enhance the performance of membranes by increasing their efficiency, selectivity, and reducing energy consumption and footprint. Adsorptive membranes, which integrate adsorption and membrane technologies, offer a promising approach to address the drawbacks of standalone membranes. By incorporating specific materials into the membrane matrix, composite membranes have demonstrated improved permeability, selectivity, and reduced pressure requirements, all while maintaining effective pollutant rejection. Researchers have explored different adsorbents, including emerging materials such as ionic liquids (ILs), deep eutectic solvents (DESs), and graphene oxide (GO), for embedding into membranes and utilizing them in various applications. This paper aims to discuss the existing challenges in the desalination process and focus on how these materials can help overcome these challenges. It will also provide a comprehensive review of studies that have reported the successful incorporation of ILs, DESs, and GO into membranes to fabricate adsorptive membranes for desalination. Additionally, the paper will highlight both the current and anticipated challenges in this field, as well as present prospects, and provide recommendations for further advancements.
ABSTRACT
The emergence of antibiotics in water has been globally recognized as a critical pollution issue. Antibiotics (such as Ciprofloxacin (CPFX) pose a serious threat to humans and to the ecosystem due to its accumulation in water sources which can lead to chronic health problems and endanger aquatic life. It is therefore crucial to properly remove them from water. In this work, a nano-composite adsorptive membrane based on Zirconium Phosphate (ZrP) adsorbent supported on Polyethersulfone (PES) was synthesized and evaluated for the removal of CPFX from synthetic aqueous solutions. The membranes described here showed a very high antibiotic removal rate. The effect of various parameters such as the initial concentration of the antibiotic, the adsorbent dosage, contact time, pH, and temperature was studied. The equilibrium data were found to reasonably best fit with the Temkin isotherm model. The membranes showed a high ciprofloxacin removal (99.7%) as opposed to (68%) when PES membrane alone was used. Moreover, a significant improvement in the membrane's water flux (100.84 L/m2.h) and permeability (97.62 L/m2.hr.bar) were noticed as opposed to pure PES membrane's flux and permeability. The adsorptive membranes were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET). The results confirmed the successful formation of ZrP nanoparticles adsorbent within the membrane matrix, and with enhanced hydrophilic properties. The membrane was successfully regenerated and reused up to 5 times. The results of this work showed the potential of such membranes for the removal of ciprofloxacin and at a high efficiency.
