Graphene Quantum Dot-Added Thin-Film Composite Membrane with Advanced Nanofibrous Support for Forward Osmosis

Abstract

Forward osmosis (FO) technology for desalination has been extensively studied due to its immense benefits over conventionally used reverse osmosis. However, there are some challenges in this process such as a high reverse solute flux (RSF), low water flux, and poor chlorine resistance that must be properly addressed. These challenges in the FO process can be resolved through proper membrane design. This study describes the fabrication of thin-film composite (TFC) membranes with polyethersulfone solution blown-spun (SBS) nanofiber support and an incorporated selective layer of graphene quantum dots (GQDs). This is the first study to sustainably develop GQDs from banyan tree leaves for water treatment and to examine the chlorine resistance of a TFC FO membrane with SBS nanofiber support. Successful GQD formation was confirmed with different characterizations. The performance of the GQD-TFC-FO membrane was studied in terms of flux, long-term stability, and chlorine resistance. It was observed that the membrane with 0.05 wt.% of B-GQDs exhibited increased surface smoothness, hydrophilicity, water flux, salt rejection, and chlorine resistance, along with a low RSF and reduced solute flux compared with that of neat TFC membranes. The improvement can be attributed to the presence of GQDs in the polyamide layer and the utilization of SBS nanofibrous support in the TFC membrane. A simulation study was also carried out to validate the experimental data. The developed membrane has great potential in desalination and water treatment applications.

Forward Osmosis Membrane: Review of Fabrication, Modification, Challenges and Potential

“…Now with FO limitations requiring the replacement of membranes after a certain amount of time, we are pleased to provide future solutions to these limitations and thus become new research directions. To create FO membranes that are more effective, reliable, and affordable, future research should concentrate on: (I) scaling up the manufacture of eco-friendly membranes, (II) lowering the cost of the membrane materials by utilizing material residue (e.g., eggshells [193]) and green solvents (e.g., dihydrolevoglucosenone [194], ionic liquids [195]), and (III) adding novel sustainable nanomaterials in a substrate and/or the thin selective layer (e.g., carbon quantum dots [196], graphene quantum dots [197]). Although there is little information on the conversion of FO membranes into sustainable membranes, future development of FO membranes should take into account these sustainable materials.…”

Sustainable Preparation of Graphene Quantum Dots from Leaves of Date Palm Tree

“…The results obtained from the above-stated research works motivated us for the research whether we can develop GQDs from renewable, inexpensive, natural, and sustainable sources like green plants, which are the basis of most of the world’s ecologies. A few studies were also carried out to develop GQDs from Eucalyptus tree leaves and Banyan tree leaves. − Certain polysaccharides, proteins, biomolecules, and enzymes in plants possess a great ability to carry out reduction and capping of nonbiocompatible materials. Plant-derived materials have been noted to be an excellent source for the green synthesis of carbon-based nanomaterials, as these materials have increased carbon amounts to synthesize the carbon nanostructured materials. , …”

Date Palm Tree Leaf-Derived Cellulose Nanocrystal Incorporated Thin-Film Composite forward Osmosis Membranes for Produced Water Treatment

“…Hence, FO processes are more reliable in PW treatment as compared to the RO process [ 25 , 26 , 27 ]. Although FO membranes exhibit less fouling than the membrane technologies utilizing pressure, their impact is nevertheless substantial [ 28 , 29 ]. Fouling in the FO system can be reduced through physical cleaning, chemical cleaning, back washing, air scouring, pretreatment, and antifouling coatings [ 30 ].…”