Synthesis route for the fabrication of nanocomposite membranes

There has been an ongoing need to develop polymer materials with increased performance as proton exchange membranes (PEMs) for middle- and high-temperature fuel cells. Poly(vinyl alcohol) (PVA) is a highly hydrophilic and chemically stable polymer bearing hydroxyl groups, which can be further altered. Protic ionic liquids (proticILs) have been found to be an effective modifying polymer agent used as a proton carrier providing PEMs’ desirable proton conductivity at high temperatures and under anhydrous conditions. In this study, the novel synthesis route of PVA grafted with fluorinated protic ionic liquids bearing sulfo groups (–SO3H) was elaborated. The polymer functionalization with fluorinated proticILs was achieved by the following approaches: (i) the PVA acylation and subsequent reaction with fluorinated sultones and (ii) free-radical polymerization reaction of vinyl acetate derivatives modified with 1-methylimidazole and sultones. These modifications resulted in the PVA being chemically modified with ionic liquids of protic character. The successfully grafted PVA has been characterized using 1H, 19F, and 13C-NMR and FTIR-ATR. The presented synthesis route is a novel approach to PVA functionalization with imidazole-based fluorinated ionic liquids with sulfo groups.

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A Comprehensive Review of Polymeric Wastewater Purification Membranes

Journal of Composites Science ◽

10.3390/jcs5060162 ◽

2021 ◽

Vol 5 (6) ◽

pp. 162

Author(s):

Rasmeet Singh ◽

Mandeep Singh ◽

Nisha Kumari ◽

Janak ◽

Sthitapragyan Maharana ◽

...

Keyword(s):

Graphene Oxide ◽

Pore Formation ◽

Inorganic Materials ◽

Special Focus ◽

Nanocomposite Membranes ◽

Wastewater Purification ◽

Comprehensive Review ◽

Synthetic Membranes ◽

Purification Membranes ◽

Thermal And Chemical Stability

Synthetic membranes are currently employed for multiple separation applications in various industries. They may have been prepared from organic or inorganic materials. Present research majorly focuses on polymeric (i.e., organic) membranes because they show better flexibility, pore formation mechanism, and thermal and chemical stability, and demand less area for installation. Dendritic, carbon nanotube, graphene and graphene oxide, metal and metal oxide, zwitter-ionic, and zeolite-based membranes are among the most promised water treatment membranes. This paper critically reviews the ongoing developments to utilize nanocomposite membranes to purify water. Various membranes have been reported to study their resistance and fouling properties. A special focus is given towards multiple ways in which these nanocomposite membranes can be employed. Therefore, this review provides a platform to develop the awareness of current research and motivate its readers to make further progress for utilizing nanocomposite membranes in water purification.

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A Review on Polymer Nanocomposites and Their Effective Applications in Membranes and Adsorbents for Water Treatment and Gas Separation

Membranes ◽

10.3390/membranes11020139 ◽

2021 ◽

Vol 11 (2) ◽

pp. 139

Author(s):

Oluranti Agboola ◽

Ojo Sunday Isaac Fayomi ◽

Ayoola Ayodeji ◽

Augustine Omoniyi Ayeni ◽

Edith E. Alagbe ◽

...

Keyword(s):

Greenhouse Gases ◽

Polymer Nanocomposites ◽

Gas Separation ◽

Rapid Growth ◽

Dye Removal ◽

Anthropogenic Activities ◽

Polymer Nanocomposite ◽

Population Increase ◽

Nanocomposite Membranes

Globally, environmental challenges have been recognised as a matter of concern. Among these challenges are the reduced availability and quality of drinking water, and greenhouse gases that give rise to change in climate by entrapping heat, which result in respirational illness from smog and air pollution. Globally, the rate of demand for the use of freshwater has outgrown the rate of population increase; as the rapid growth in town and cities place a huge pressure on neighbouring water resources. Besides, the rapid growth in anthropogenic activities, such as the generation of energy and its conveyance, release carbon dioxide and other greenhouse gases, warming the planet. Polymer nanocomposite has played a significant role in finding solutions to current environmental problems. It has found interest due to its high potential for the reduction of gas emission, and elimination of pollutants, heavy metals, dyes, and oil in wastewater. The revolution of integrating developed novel nanomaterials such as nanoparticles, carbon nanotubes, nanofibers and activated carbon, in polymers, have instigated revitalizing and favourable inventive nanotechnologies for the treatment of wastewater and gas separation. This review discusses the effective employment of polymer nanocomposites for environmental utilizations. Polymer nanocomposite membranes for wastewater treatment and gas separation were reviewed together with their mechanisms. The use of polymer nanocomposites as an adsorbent for toxic metals ions removal and an adsorbent for dye removal were also discussed, together with the mechanism of the adsorption process. Patents in the utilization of innovative polymeric nanocomposite membranes for environmental utilizations were discussed.

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Efficient Chitosan/Nitrogen-Doped Reduced Graphene Oxide Composite Membranes for Direct Alkaline Ethanol Fuel Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22041740 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1740 ◽

Cited By ~ 1

Author(s):

Selestina Gorgieva ◽

Azra Osmić ◽

Silvo Hribernik ◽

Mojca Božič ◽

Jurij Svete ◽

...

Keyword(s):

Fuel Cells ◽

Composite Membranes ◽

Nanocomposite Membranes ◽

Ethanol Fuel ◽

Direct Ethanol Fuel Cells ◽

Graphene Oxides ◽

Reduced Graphene ◽

Structure Morphology ◽

Graphene Derivatives ◽

Doped Graphene

Herein, we prepared a series of nanocomposite membranes based on chitosan (CS) and three compositionally and structurally different N-doped graphene derivatives. Two-dimensional (2D) and quasi 1D N-doped reduced graphene oxides (N-rGO) and nanoribbons (N-rGONRs), as well as 3D porous N-doped graphitic polyenaminone particles (N-pEAO), were synthesized and characterized fully to confirm their graphitic structure, morphology, and nitrogen (pyridinic, pyrrolic, and quaternary or graphitic) group contents. The largest (0.07%) loading of N-doped graphene derivatives impacted the morphology of the CS membrane significantly, reducing the crystallinity, tensile properties, and the KOH uptake, and increasing (by almost 10-fold) the ethanol permeability. Within direct alkaline ethanol test cells, it was found that CS/N rGONRs (0.07 %) membrane (Pmax. = 3.7 mWcm−2) outperformed the pristine CS membrane significantly (Pmax. = 2.2 mWcm−2), suggesting the potential of the newly proposed membranes for application in direct ethanol fuel cells.

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