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ion-exchange-membranes
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The effects of porosity distribution variation in GDL on PEM fuel cell performance
, Article Second International Conference on Fuel Cell Science, Engineering and Technology, Rochester, NY, 14 June 2004 through 16 June 2004 ; 2004 , Pages 587-594 ; 0791841650 (ISBN); 9780791841655 (ISBN) ; Farhanieh, B ; Saievar Iranizad, E ; Sharif University of Technology
American Society of Mechanical Engineers
2004
Abstract
Gas diffusion layers are one of the important parts of the PEM fuel cell as they serve to transport the reactant gases to the catalyst layer. Porosity of this layer has a large effect on the PEM fuel cell performance. The spatial variation in porosity arises due to two effects: 1. Compression of the electrode on the solid landing areas and 2. Water produced at the cathode side of gas diffusion layers. Both of these factors change the porosity of gas diffusion layers and affects fuel cell performance. To implement this performance analysis, a mathematical model which considers oxygen and hydrogen mass fraction in gas diffusion layer and the electrical current density in the catalyst layer,...
Oppositely charged MXene fibers as a highly efficient osmotic power generator from sea and river water
, Article Journal of Materials Chemistry A ; Volume 10, Issue 46 , 2022 , Pages 24915-24926 ; 20507488 (ISSN) ; Esfandiar, A ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
Ion-exchange membrane-based reverse electrodialysis (RED) shows great potential for harvesting osmotic energy from seawater and converting it to electricity. However, their low energy conversion efficiency and huge ionic resistance hinder their application on large scales. The implementation of nanofluidic channels in RED devices can significantly improve the performance of osmotic power generators due to their selective and fast ion transport. However, technical challenges in scalable processing at the nanoscale and ion-selective membranes restrict their development in economically viable generators. Here, we report fibrous-based channels as positively and negatively charged MXene fibers...
Investigation on various types of ion-exchange membranes in vanadium redox flow batteries: Experiment and modeling
, Article Journal of Energy Storage ; Volume 54 , 2022 ; 2352152X (ISSN) ; Rahimi, M ; Molaei Dehkordi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Choosing the appropriate ion exchange membrane in vanadium redox flow batteries plays an important role in achieving optimal system performance. In this article, the implementation of commercial cation exchange membranes (Nafion 115, Nafion 117, and Nafion 212), anion exchange membranes (FAP 450 and QA-PFE), and the combination of them are investigated. In this regard, the effects of membrane type, thickness, electrical conductivity, and the transfer of vanadium species at different current densities are examined carefully. In addition, the influences of the flow rate and the concentration of electrolytes are investigated using a comprehensive developed model. The model predictions are...
Preparation of Polymeric Ion-Exchange Membrane for Water Desalination
, M.Sc. Thesis Sharif University of Technology ; Musavi, Abbas (Supervisor)
Abstract
In present research work, methods of preparing ion exchange membranes, especially anion exchange membranes, were studied and chemical modification of polysulfone was chosen as a safe and economical method for preparing anion exchange membranes. The chloromethylated polysulfone was characterized by HNMR spectroscopy and functionalization degree was determined according to peak area integration. Membranes were produced by mixing and amination of the chloromethylated and normal polysulfone (40-100% wt). Morphology and chemical structure of membranes were investigated by SEM images and FTIR spectroscopy.The ionic conductivity, ion exchange capacity and water content of samples were measured. The...
Electrodialysis of Llithium from Spent Lithium-Ion Battries
, M.Sc. Thesis Sharif University of Technology ; Askari, Masoud (Supervisor)
Abstract
In this study, Lithium recovery process from lithium-ion battery was investigated by electrodialysis method. First, the cathode of the battery was leached in NMP to separate cathode from aluminum foil. Then, the cathode was leached in sulfuric acid with concentration 3.25 M and 10 volume percent hydrogen peroxide that pulp density was 55 g/L at 60°C for 100 minutes. in the next step, an electrodialysis cell was designed and created to recover lithium. And the influence of time, voltage, flow rate of feed solution, concentration of electrode solution and concentration of feed solution on process was investigated. Purpose of this project were investigated lithium ion recovery rate, lithium...
Novel high-performance nanocomposite proton exchange membranes based on poly (ether sulfone)
, Article Renewable Energy ; Volume 35, Issue 1 , 2010 , Pages 226-231 ; 09601481 (ISSN) ; Dashtimoghadam, E ; Ghaffarian, S.R ; Hasani Sadrabadi, M.H ; Heidari, M ; Moaddel, H ; Sharif University of Technology
2010
Abstract
In the present research, proton exchange membranes based on partially sulfonated poly (ether sulfone) (S-PES) with various degrees of sulfonation were synthesized. It was found that the increasing of sulfonation degree up to 40% results in the enhancement of water uptake, ion exchange capacity and proton conductivity properties of the prepared membranes to 28.1%, 1.59 meq g -1, and 0.145 S cm -1, respectively. Afterwards, nanocomposite membranes based on S-PES (at the predetermined optimum sulfonation degree) containing various loading weights of organically treated montmorillonite (OMMT) were prepared via the solution intercalation technique. X-ray diffraction patterns revealed the...
Polyelectrolyte nanocomposite membranes using imidazole-functionalized nanosilica for fuel cell applications
, Article Journal of Macromolecular Science, Part B: Physics ; Volume 54, Issue 1 , Nov , 2015 , Pages 17-31 ; 00222348 (ISSN) ; Ghaffarian, S. R ; Nouri, M ; Jaafarnia, E ; Haghighi, A. H ; Sharif University of Technology
Taylor and Francis Inc
2015
Abstract
The preparation and characterization of a new type of nanocomposite polyelectrolyte membrane, based on DuPont Nafion/imidazole-modified nanosilica (Im-Si), for direct methanol fuel cell applications is described. Related to the interactions between the protonated imidazole groups, grafted on the surface of nanosilica, and negatively charged sulfonic acid groups of Nafion, new electrostatic interactions can be formed in the interface of Nafion and Im-Si which result in both lower methanol permeability and also higher proton conductivity. Physical characteristics of these manufactured nanocomposite membranes were investigated by scanning electron microscopy, thermogravimetry analysis,...
Effect of casting solvent on the characteristics of nafion/TiO2 nanocomposite membranes for microbial fuel cell application
, Article International Journal of Hydrogen Energy ; Volume 41, Issue 1 , 2016 , Pages 476-482 ; 03603199 (ISSN) ; Mousavi, S. A ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
Synthesis and characterization of Nafion/TiO2 membranes (TiO2 1 wt%) with different solvents (DMF, DMAc, NMP) for proton exchange membrane operating at Microbial Fuel Cell (MFC) was investigated in this study. Nanocomposite membranes are studied due to their better physical properties and higher production voltage in comparison with Nafion 112 in MFC systems. Nafion/TiO2 nanocomposite membranes were prepared by solution casting Method. The structures of membranes were investigated by Scanning Electron Microscopy (SEM). In addition, water uptake, proton conductivity, and ion exchange capacity (IEC) of membranes were measured and compared with Nafion 112 in microbial fuel cell. The...
Simulation of an innovative flow-field design based on a bio inspired pattern for PEM fuel cells
, Article Renewable Energy ; Volume 41 , 2012 , Pages 86-95 ; 09601481 (ISSN) ; Arbabi, F ; Moghaddam, G. K ; Sharif University of Technology
2012
Abstract
Proton exchange membrane (PEM) fuel cell performance is directly related to the bipolar plate design and their channels pattern. Power enhancements can be achieved by optimal design of the type, size, or patterns of the channels. It has been realized that the bipolar plate design has significant role on reactant transport as well as water management in a PEM Fuel cell. Present work concentrates on improvements in the fuel cell performance by optimization of flow-field design and channels configurations. A three-dimensional, multi-component numerical model of flow distribution based on Navier-Stokes equations using individual computer code is presented. The simulation results showed excellent...