Emerging advances of composite membranes for seawater pre-treatment: a review

As the population continues to grow, the preservation of the world's water resources is becoming a serious challenge. The seawater desalination process is considered a sustainable option for the future. The two most common technologies used in desalination are reverse osmosis (RO) and membrane distillation (MD). However, membrane fouling caused by the accumulation of contaminants on the membrane surface is an emerging and growing problem. A pre-treatment stage is required to reach optimal efficiency during the desalination process since this stage is crucial for a successful desalination process. In this regard, the development of new material-based composite membranes has the potential to upgrade the anti-fouling features of RO membranes thereby enhancing desalination efficiency due to their high permeability, hydrophilicity, selectivity mechanical strength, thermal stability, and anti-bacterial properties. The objective of this review is to present various techniques for seawater pre-treatment. The results of the use of several membrane types and methods of modification have also been discussed. The performance of composite membranes for seawater pre-treatment is defined and the future perspectives have been highlighted.

Surface Engineering of a Bioartificial Membrane for Its Application in Bioengineering Devices

Membrane technology is playing a crucial role in cutting-edge innovations in the biomedical field. One such innovation is the surface engineering of a membrane for enhanced longevity, efficient separation, and better throughput. Hence, surface engineering is widely used while developing membranes for its use in bioartificial organ development, separation processes, extracorporeal devices, etc. Chemical-based surface modifications are usually performed by functional group/biomolecule grafting, surface moiety modification, and altercation of hydrophilic and hydrophobic properties. Further, creation of micro/nanogrooves, pillars, channel networks, and other topologies is achieved to modify physio-mechanical processes. These surface modifications facilitate improved cellular attachment, directional migration, and communication among the neighboring cells and enhanced diffusional transport of nutrients, gases, and waste across the membrane. These modifications, apart from improving functional efficiency, also help in overcoming fouling issues, biofilm formation, and infection incidences. Multiple strategies are adopted, like lysozyme enzymatic action, topographical modifications, nanomaterial coating, and antibiotic/antibacterial agent doping in the membrane to counter the challenges of biofilm formation, fouling challenges, and microbial invasion. Therefore, in the current review, we have comprehensibly discussed different types of membranes, their fabrication and surface modifications, antifouling/antibacterial strategies, and their applications in bioengineering. Thus, this review would benefit bioengineers and membrane scientists who aim to improve membranes for applications in tissue engineering, bioseparation, extra corporeal membrane devices, wound healing, and others.

An anti-fouling poly(vinylidene fluoride) hybrid membrane blended with functionalized ZrO2 nanoparticles for efficient oil/water separation

Functionalized nanoparticle of ZrO₂ grafted with poly(N-acryloylmorpholine) was synthesized via radical grafting polymerization. The nanoparticle was directly blended with PVDF to prepare hybrid membrane. The efficient separation of oil/water mixture is established.