Modified Electrospun Membranes Using Different Nanomaterials for Membrane Distillation

Abstract

Obtaining fresh drinking water is a challenge directly related to the change in agricultural, industrial, and societal demands and pressure. Therefore, the sustainable treatment of saline water to get clean water is a major requirement for human survival. In this review, we have detailed the use of electrospun nanofiber-based membranes (ENMs) for water reclamation improvements with respect to physical and chemical modifications. Although membrane distillation (MD) has been considered a low-cost water reclamation process, especially with the availability of low-grade waste heat sources, significant improvements are still required in terms of preparing efficient membranes with enhanced water flux, anti-fouling, and anti-scaling characteristics. In particular, different types of nanomaterials have been explored as guest molecules for electrospinning with different polymers. Nanomaterials such as metallic organic frameworks (MOFs), zeolites, dioxides, carbon nanotubes (CNTs), etc., have opened unprecedented perspectives for the implementation of the MD process. The integration of nanofillers gives appropriate characteristics to the MD membranes by changing their chemical and physical properties, which significantly enhances energy efficiency without impacting the economic costs. Here, we provide a comprehensive overview of the state-of-the-art status, the opportunities, open challenges, and pitfalls of the emerging field of modified ENMs using different nanomaterials for desalination applications.

Enhancing Mechanical Properties and Flux of Nanofibre Membranes for Water Filtration

“…Treatments that use crosslinking mechanisms to enhance mechanical strength are chemical crosslinking, physical crosslinking, and enzymatic crosslinking. For instance, to chemically crosslink gelatine nanofibre, glutaraldehyde often uses as a crosslinking agent [ 36 ]. The mechanism of chemical crosslinking is in an earlier paragraph.…”

“…Recent advances in experimental and computational development have become potent tools for exploring and engineering the modifications needed to increase the strength of nanofibre membranes. Khatri et al (2023) focus on enhancing nanofibre membranes for membrane distillation (MD) through nanofibre composite structure [ 36 ]. A sufficient tensile strength has to be constructed and attached to membrane modules as operational pressures are substantially lower than those for RO, UF, and MF [ 59 ].…”

Omniphobic, Bilayer Carbon Nanotube-Immobilized Fluorinated (FAS) Membranes for Bioethanol Recovery at High Concentrations via Membrane Distillation

“…For example, coating of fluorinated-decyl polyhedral oligomeric silsesquioxane (FD-POSS) , and fluoroalkyl silane (FAS) , on different surfaces have dramatically improved the contact angles of water . Moreover, nanocarbons such as carbon nanotubes (CNTs), graphene, or carbon quantum dots have been used to modify MD membranes due to their inherent hydrophobicity and are also capable of modifying surface roughness. − They can also undergo functionalization to modify their surface hydrophobicity, , making them highly adaptable for tailored applications, , and our previous work on making hydrophobic membrane by incorporating CNT has shown excellent vapor flux and selectivity. ,, …”

Recent Advances in Dopamine-Based Membrane Surface Modification and Its Membrane Distillation Applications

“…Theoretically, only water vapor can pass through the membrane pore, and it can achieve 100% interception of ions, macromolecules, colloids, cells and other non-volatile substances [1][2][3]. Moreover, it can collect renewable energy, including solar energy, geothermal energy and low-grade waste heat, as a heat source to provide heat for the feed side, which means that the process has higher energy efficiency and lower operating costs [4][5][6]. Due to these advantages of membrane distillation, the process has great application potential in the fields of seawater desalination, wastewater treatment, ultrapure water production, the food industry and the medical industry [7,8].…”