Exploring the potential of photocatalytic dual layered hollow fiber membranes incorporated with hybrid titania nanotube-boron for agricultural wastewater reclamation

Low-cost photocatalytic membrane modified with green heterojunction TiO2/ZnO nanoparticles prepared from waste

The combination of photocatalysis and membrane procedures represents a promising approach for water treatment. This study utilized green synthesis methods to produce TiO2 nanoparticles (NPs) using Pomegranate extract and ZnO nanoparticles using Tangerine extract. These nanoparticles were then incorporated into a polyvinyl chloride (PVC) nanocomposite photocatalytic membrane. Different devices were used to examine the properties of nanocomposite membranes. The prepared membranes' morphology was examined using atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM). The hydrophilicity of the membrane surface was assessed through the measurement of contact angle, while the crystal structure and chemical bonding were analyzed using Raman and Fourier transform infrared spectroscopy (FT-IR). The study also encompassed an examination of the mechanical properties. The hydrophilicity of the modified membrane exhibited a significant improvement. Additionally, there was an observed increase in both the pure water flux and rejection values. The photocatalytic activity of the membrane was found to be enhanced when exposed to sunlight as compared to when kept in the dark. The TiO2/ZnO nanocomposites membrane exhibited the highest level of photocatalytic degradation, achieving a rejection rate of 98.7% compared to the unmodified membrane. Therefore, it was determined that the TiO2/ZnO nanocomposites membrane exhibited superior performance to the other membranes assessed. The potential utility of our research lies in its application within the water treatment industry, specifically as an effective technique for modifying PVC membranes.

Modification of Liquid Separation Membranes Using Multidimensional Nanomaterials: Revealing the Roles of Dimension Based on Classical Titanium Dioxide

Membrane technology has become increasingly popular and important for separation processes in industries, as well as for desalination and wastewater treatment. Over the last decade, the merger of nanotechnology and membrane technology in the development of nanocomposite membranes has emerged as a rapidly expanding research area. The key motivation driving the development of nanocomposite membranes is the pursuit of high-performance liquid separation membranes that can address the bottlenecks of conventionally used polymeric membranes. Nanostructured materials in the form of zero to three-dimensions exhibit unique dimension-dependent morphology and topology that have triggered considerable attention in various fields. While the surface hydrophilicity, antibacterial, and photocatalytic properties of TiO₂ are particularly attractive for liquid separation membranes, the geometry-dependent properties of the nanocomposite membrane can be further fine-tuned by selecting the nanostructures with the right dimension. This review aims to provide an overview and comments on the state-of-the-art modifications of liquid separation membrane using TiO₂ as a classical example of multidimensional nanomaterials. The performances of TiO₂-incorporated nanocomposite membranes are discussed with attention placed on the special features rendered by their structures and dimensions. The innovations and breakthroughs made in the synthesis and modifications of structure-controlled TiO₂ and its composites have enabled fascinating and advantageous properties for the development of high-performance nanocomposite membranes for liquid separation.

Membrane technology for pesticide removal from aquatic environment: Status quo and way forward

The noxious side effects of pesticides on human health and environment have prompted the search of effective and reliable treatment techniques for pesticide removal. The removal of pesticides can be accomplished through physical, chemical and biologicals. Physical approaches such as filtration and adsorption are prevailing pesticide removal strategies on account of their effectiveness and ease of operation. Membrane-based filtration technology has been recognized as a promising water and wastewater treatment approach that can be used for a wide range of organic micropollutants including pesticides. Nanofiltration (NF), reverse osmosis (RO) and forward osmosis (FO) have been increasingly explored for pesticide removal from aquatic environment owing to their versatility and high treatment efficiencies. This review looks into the remedial strategies of pesticides from aqueous environment using membrane-based processes. The potentials and applications of three prevailing membrane processes, namely NF, RO and FO for the treatment of pesticide-containing wastewater are discussed in terms of the development of advanced membranes, separation mechanisms and system design. The challenges in regards to the practical implementation of membrane-based processes for pesticide remediation are identified. The corresponding research directions and way forward are highlighted. An in depth understanding of the pesticide nature, water chemistry and the pesticide-membrane interactions is the key to achieving high pesticide removal efficiency. The integration of membrane technology and conventional removal technologies represents a new dimension and the future direction for the treatment of wastewater containing recalcitrant pesticides.

Photocatalytic nanohybrid membranes for highly efficient wastewater treatment: A comprehensive review

Wastewater is inevitably generated from human activities as part of the life cycle chain that potentially damages the environment. The integration of photocatalytic reaction and membrane separation for wastewater treatment has gained great attention in recent studies. However, there are still many technical limitations for its application such as toxic metal release, catalyst deactivation, fouling/biofouling, polymer disintegration, and separation performance decline. Different types, combinations, and modifications of photocatalysts material combined with membranes such as semiconductor metal oxides, binary/ternary hybrid metal oxides, elemental doped semiconductors, and metal-organic frameworks (MOFs) for improving the performance and compatibility are presented and discussed. The strategies of incorporating photocatalysts into membrane matrix for pursuing the most stable membrane integrity, high photocatalytic efficiency, and excellent perm-selectivity performance in the very recent studies were discussed. This review also outlines the performance enhancement of photocatalytic membranes (PMs) in wastewater treatment and its potential for water reclamation. Photocatalysts enhanced membrane separation by inducing anti-fouling and self-cleaning properties as well as antibacterial activity. Based on the reviewed study, PMs are possible to achieve complete removal of emerging contaminants and ∼99% reduction of bacterial colony that leading on the zero liquid discharge (ZLD). However, the intensive exposure of photo-induced radicals potentially damages the polymeric membrane. Therefore, future studies should be focused on fabricating chemically stable host-membrane material. Moreover, the light source and the membrane module design for the practical application by considering the hydrodynamic and cost-efficiency should be a concern for technology diffusion to the industrial-scale application.