Integration of silver nanoparticles and microcurrent for water filtration

Nanoparticles functionalized ceramic membranes: fabrication, surface modification, and performance

Membrane technologies are used intensively for desalination and wastewater treatment. Water filtration using ceramic membranes exhibited high performance compared with polymeric membranes due to various properties such as high resistance to fouling, permeability, rejection rate, and chemical stability. Recently, the performance of nanocomposite ceramic membranes was improved due to the development in nanotechnology. This article focusses on the development of porous ceramic membranes and nanomaterial functionalized ceramic membranes for water filtration applications. At the beginning, various fabrication methods of ceramic membranes were described, and the effect of surface modification techniques on the membrane intrinsic properties was reviewed. Then, the performance of nanoparticles functionalized ceramic membranes was evaluated in terms of physicochemical properties, rejection rate, and water permeability. This work can help new entrants and established researchers to become familiar with the current challenges and developments of nanoparticle-incorporated ceramic membranes for water filtration applications.

Effect of Silver Nanoparticles on the Morphology of Toxoplasma gondii and Salmonella braenderup

The study of silver nanoparticles (AgNPs) has recently increased due to the different antimicrobial properties that have been evaluated. Studies have shown that AgNPs decrease the cell viability of some parasitic species and inhibit bacterial growth and biofilm formation. Toxoplasma gondii is a parasite with different stages of development including the oocyst, and it can survive in the environment for a long time generating contamination of vegetables and water. This parasite has the ability to generate congenital toxoplasmosis and chorioretinitis in humans. Another human pathogen present in water is Salmonella braenderup, this bacterium, when consumed, causes gastroenteritis and typhoid fever. We evaluate the affectation that causes the AgNPs in oocysts of T. gondii and S. braenderup using fluorescence microscopy and scanning electron microscopy techniques. The results showed that at different ratios of AgNPs and microorganisms, as well as at different exposure time during the treatments, morphological alteration of the cell structure of oocysts of T. gondii and S. braenderup was evidenced, suggesting a potential treatment method for the inhibition of the viability of these microorganisms.

A Review on Porous Polymeric Membrane Preparation. Part I: Production Techniques with Polysulfone and Poly (Vinylidene Fluoride)

Porous polymeric membranes have emerged as the core technology in the field of separation. But some challenges remain for several methods used for membrane fabrication, suggesting the need for a critical review of the literature. We present here an overview on porous polymeric membrane preparation and characterization for two commonly used polymers: polysulfone and poly (vinylidene fluoride). Five different methods for membrane fabrication are introduced: non-solvent induced phase separation, vapor-induced phase separation, electrospinning, track etching and sintering. The key factors of each method are discussed, including the solvent and non-solvent system type and composition, the polymer solution composition and concentration, the processing parameters, and the ambient conditions. To evaluate these methods, a brief description on membrane characterization is given related to morphology and performance. One objective of this review is to present the basics for selecting an appropriate method and membrane fabrication systems with appropriate processing conditions to produce membranes with the desired morphology, performance and stability, as well as to select the best methods to determine these properties.