Adsorptive Membranes Incorporating Ionic Liquids (ILs), Deep Eutectic Solvents (DESs) or Graphene Oxide (GO) for Metal Salts Extraction from Aqueous Feed

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.

Thin Film Composite Membrane Comprising Ionic Liquid/Graphene Oxide in the Selective Layer for Enhanced CO2 Separation

“…In recent years, ionic liquids (ILs)/GO nanosheet composite additives have been utilized to overcome the above problems with GO and improve the gas separation performance of polymer membranes. − ILs are semiorganic salts consisting of one cation and one anion that melt around room temperature and are characterized by low vapor pressure, versatile solubility, and good thermal stability. − In addition, the tunability of ILs by changing the type of anion and cation has made them desirable for various applications, including gas separation. − Favorable interactions between quadrupolar CO 2 molecules and ILs lead to high CO 2 solubility and selectivity compared to other light gases such as methane (CH 4 ) and nitrogen (N 2 ). ,, Karunakaran et al fabricated a high-flux and CO 2 selective ultrathin composite membrane by incorporating a blend of imidazolium-based ionic liquids and GO into a porous polyacrylonitrile (PAN) matrix. The membrane showed high CO 2 permeance and CO 2 /N 2 selectivity that surpasses the upper bound of IL membranes for CO 2 /N 2 separation.…”

Graphene Oxide–Polyphenylsulfone Nanocomposite Beads for Paracetamol Removal from Aqueous Solution

“…Among these polymers, polyphenylsulfone (PPSU) has garnered considerable attention for its compatibility with GO and its potential to enhance the overall adsorption efficiency. Various techniques, such as high internal phase emulsions, have been employed to produce beads and spherical nanocomposites [ 35 , 37 ]. However, these methods often involve high-temperature processes, protracted and intricate procedures, which can hinder their practicality.…”