The anion exchange membrane find application in diverse process such as electrodialysis, diffusion analysis, membrane electrolysis, reverse osmosis and membrane fuel cells, which are energy, resource and environment saving. The development of ion-exchange membrane of high chemical, mechanical and thermal stability, which meet growing demand of the aforementioned processes, is of great importance. This paper deals with the determination of the membrane permselectivity coefficient of anion exchange membranes for concentration of citric acid using electrodialysis process. The permselectivity coefficient of three types of commercial anion exchange membranes; Neosepta ACS(Tokuyama, Japan), Neosepta AHA2(Tokuyama, Japan) and 204UZR412(Ionics. Inc., USA) were compared in consideration to the physicochemical data of these membranes published so far are not adequate to their industrial application particularly for citric acid concentration. The permselectivity coefficient is the ability of anion exchange ...

In the current research, polyvinylchloride based mixed matrix heterogeneous anion exchange membranes were prepared by a solution casting technique. Titanium dioxide nanoparticles were also utilized as inorganic filler additive in the membrane fabrication. The effect of TiO2 nanoparticles concentration in the casting solution on the membrane physico-chemical properties was studied. Membrane water content was decreased by an increase of nanoparticle concentration. Ion exchange capacity was also improved initially by an increase of nanoparticle content ratio and then slightly decreased. The membrane fixed ionic concentration, membrane potential, transport number and permselectivity were all increased by an increase of additive loading ratio. The membrane ionic permeability was enhanced initially by an increase of nanoparticle concentration up to 0.5 %wt in the membrane matrix and then decreased by more additive content ratio from 0.5 to 4 %wt. Membrane ionic resistance was declined by using TiO2

The formation of gypsum (CaSO4·2H2O) scale in ion-exchange membranes was investigated under a Donnan exchange regime. Two types of anion exchange membranes (AEM), homogeneous AMV and heterogeneous MA-40, were used for the study. Counter-ion flux, scaling-cation concentration in the fouled membrane and membrane potential served as indicators for membrane scaling. Locations of scaling domains were dependent on the membrane structure, and lead to different effects on the membrane performance. Scaling in the homogeneous membrane was mainly characterized by surface deposits, resulting in a moderate decrease of the counter-ion flux. On the other hand, the heterogeneous membrane showed a high degree of internal precipitation resulting in a complete clogging of the membrane, thus leading to earlier and more severe decline in counter-ion flux. Significant amounts of calcium were found within the fouled MA-40, supporting the other indications of internal scaling. The potential difference across the ...

New, high molecular weight poly-(fluorene-alt-tetrafluorophenylene) anion exchange membranes were synthesized by a Pd-catalyzed C-H activation method. The synthesized membranes exhibited high OH− conductivity over 100 mS cm−1, and membrane swelling could be suppressed by controlling the side chain length of the pol

A novel surface modified anion exchange membrane (AEM) was prepared by electrodeposition of graphene oxide (GO) and polydopamine (PDA) coating, aiming at improving antifouling performance and stability. The AEM was firstly modified by electrodeposition of GO and then immersed into the dopamine solution to form a thin PDA layer. The effects of GO and PDA composite modification were investigated by various analytical techniques and electrodialysis application. The [email protected] AEM ([email protected]) exhibited highly hydrophilic and negatively charged. In addition, the introduction of PDA coating helped to construct a smoother and denser composite modifying layer composed of GO and PDA, and reduced the roughness of membrane surface. Depending on these properties, the [email protected] AEM showed significant antifouling ability without compromising the desalination performance. After being fouled by 150 mg/L sodium dodecyl benzene sulfonate (SDBS) for 4 h, the desalination rate of [email protected] increased by ...

292993171 - EP 1159295 A1 2001-12-05 - METHOD OF PURIFYING WHEY OF LACTIC ACID FERMENTATION BY ELECTRODIALYSIS - [origin: US6204362B1] In a method of purifying whey separated from lactic acid fermentation liquid by electrodialysis wherein said whey contains angiotensin-converting enzyme inhibiting peptides, the improvement which comprises using an anion exchange membrane having a permeability of diffusion coefficient in the range of 3.0 to 9.0x10-6 cm/sec. An anion exchange membrane having a permeability of diffusion coefficient in the range of 5.0 to 7.0x10-6 cm/sec. is more efficiently used. The product is particularly suited to produce granules and tablets.[origin: US6204362B1] In a method of purifying whey separated from lactic acid fermentation liquid by electrodialysis wherein said whey contains angiotensin-converting enzyme inhibiting peptides, the improvement which comprises using an anion exchange membrane having a permeability of diffusion coefficient in the range of 3.0 to 9.0x10-6 cm/sec. An

All information described in this bulletin is based upon tests and data believed to be reliable. It is the users responsibility to determine performance and suitability of the products. No guarantee, expressed or implied, is made by Membranes International Inc., nor does Membranes International Inc. assume any liability for patent infringement arising from the use of these products.. ...

The purpose of this study was to develop an economical, safe and environmentally friendly electrochemical process for the conversion and recovery of Fe and H2SO4 from a FeSO4 leaching solution. For this purpose, two basic ...

In this thesis Reverse Electrodialysis (RED) is central. A RED stack comprises of alternating series of cation exchange membranes (CEMs) and anion exchange membranes (AEMs), with seawater and river water compartments between these membranes.. From the salinity gradient, energy is harvested while controlling the mixing of seawater and river water. Membranes allow selective transport of cations (CEM) and anions (AEM). A voltage difference is created due to the difference in salinity across the membrane. At the electrodes redox reactions are used, to convert ionic transport into electrical transport, to power a device.. We came up with creative strategies to prevent fouling, says Jordi Moreno. The most high-profile idea concerned the concept of breathing cells. We brought this proof of principle - confirmed earlier in lab environments by dr. ir. David Vermaas - a decisive step further. The stack is now automatically operable which is practically relevant.. In the breathing cell concept, instead ...

Our products fumasep FAB, FKB and FBM are designed and optimized for electrodialysis with bipolar membranes. The EDBM is the combination of conventional electrodialysis for salt separation with electrochemical water splitting for the conversion of a salt into its corresponding acid and base. fumasep FAB is an anion exchange membrane which is developed for very low proton crossover to receive a high concentration of acid. fumasep FKB is a cation exchange membrane optimized for high cation transport in combination with high OH- retention. fumasep FBM is a bipolar membrane, which induce the splitting of water into protons and hydroxide ions. The bipolar membrane fumasep FBM combines high selectivity and efficiency as well as high chemical stability within a broad pH range, excellent mechanical stability and low electrical resistance. It is ideally suited for the production of acid and base from the corresponding salts, as well as for innovative concepts such as biological fuel cells. The patented ...

Baranek, A., Kendrick, L., Narayanan, J., Patton, D. (2013). Quaternary Ammonium Functional Polybenzoxazines for Anion Exchange Membrane (AEM) Applications. Abstracts of Papers of the American Chemical Society, 245 ...

Galactosyl-oligosaccharides (GOS) are non-digestible oligosaccharides which are qualified as functional foods. GOS are enzymatically synthesized from lactose by transgalactosylation catalyzed by the enzyme β-galactosidase. In this study, a method for immobilization of β-galactosidase from Kluyveromyces lactis on a chromatography membrane was developed. The immobilization was performed at 4, 15 and 40°C. A strong basic anion exchange membrane was investigated. In static experiments the highest enzyme activity was measured at an immobilization procedure temperature of 15°C. The immobilization on the chromatography membranes was found to be very rapid likely due to ionic adsorption. The synthesis of GOS was carried out in a Continuous Membrane Chromatography Reactor System (CMCRS) at 40°C and pH 7.0 using 20 wt% initial lactose concentration. The chromatography membranes proved to be a good support for the continuous process at high convective flow rates in the enzyme reactor system. Up to 82 ...

The simultaneous transport of sulphuric and phosphoric acids through a polymeric membrane was investigated at steady state in a two-compartment counter-current dialyzer. For this purpose, an anion exchange membrane Neosepta-AFN (Astom Corporation, Tokyo, Japan) was used. This transport was quantified by four membrane mass transfer coefficients which are dependent upon the concentrations of both acids in the feed. These coefficients were determined by a two-step procedure. In the first step, the basic differential equations describing the dependences of the volumetric liquid flow rates and acid concentrations on the length coordinate in the individual compartments were numerically integrated. In the second step, an objective function was minimised to ensure the best coincidence between the experimental and calculated data ...

hours leached 30±7.5% (95% confidence level) of this Tot-P in litter, measured by anion exchange membrane extraction. This increased to 46.9% of apparent P release at 115 days. The released P was incorporated into microbial biomass during leaching so modifying leachate concentrations. Using liquid chloroform fumigation it was estimated that 36.2 ± 15.6% (95% confidence level) of Tot-P leached during the 115-day inundation was in the microbial biomass pool, not directly measured by AEM extraction. P leaching during initial and prolonged inundation correlated with litter Ca, Mg and total base concentration, but the initial Tot-P concentration of litter was the best predictor for P leaching, in both short-term and prolonged inundation (R2 = 0.80 and 0.93, p , 0.0001). The high P leaching rate during 24 hours suggested that P from litter during first storm events could produce a significant P flux from local catchments and contribute nutrients to downstream wetlands.. ...

A polytetrafluoroethylene-quaternary 1,4-diazabicyclo-[2.2.2]-octane polysulfone composite membrane for alkaline anion exchange membrane fuel ...

Imidazolium-functionalized styrenic copolymers have been widely studied as candidates for use as anion exchange membranes in carbon dioxide and water electrolysis systems. Recent new developments in catalytic electrode materials suggest that electrolyzers based on this technology will be commercially viable. Nevertheless, important aspects of the physicochemical behavior of these membrane materials, especially transformations occurring upon activation in strongly alkaline media, remain incompletely understood. We will discuss results from 1- and 2-D NMR, IR, IEC, and DSC studies of imidazolium-functional styrenic copolymer membrane materials recovered after activation by exposure to 1M KOH solution and reacidification in HCl. The work sheds some new light on such aspects as chemical reactions and polymer crosslinking processes occurring in strong base, although mechanistic questions remain ...

A cation exchange membrane is disclosed comprising fluorinated polymer layers which include, in order, a layer with sulfonic exchange groups, a layer with carboxylic exchange groups, and a thinner layer with carboxylic exchange groups at a greater exchange capacity than the other carboxylic layer.

This work covers the direct glucose anion exchange membrane fuel cell (AEMFC) with near-neutralstate electrolyte of 0.1 M [PO4] (tot) having two high-performing anode electrocatalysts (Pt and PtNi) at 37 degrees C and at a glucose concentration of 0.1 M. The cathode catalyst in each test was a Pt supported on carbon (60 wt.%). The PtNi/C had a total metal content of 40 wt.% and the Pt/C 60 wt.%. The operation of the AEMFC was controlled by means of an in-house made electronic load with PI-controller (i.e. a feedback controller, which has proportional and integral action on control error signal). There were two primary objectives with this study. At first, to find out how the electrode modifications of the anode (i.e. by increasing the thicknesses of these electrodes by adding extra carbon) affect the Coulombic efficiency (CE, based on the exchange of two electrons) and the specific energy (SPE, Wh kg(-1)) values of the direct glucose AEMFC. Secondly, investigate how a two-stage fuel cell system ...

Direct glucose anion exchange membrane fuel cell (AEMFC) with near-neutral-state electrolyte of 0.1 M [PO4] tot was studied with five different anode electrocatalysts (Pt, PtRu, PtNi, Au, PdAu) at a temperature of 37 oC and at a glucose concentration of 0.1 M. The cathode catalyst in each test was Pt supported on carbon (60 wt.%). Four anode electrocatalysts (supported on carbon) had a total metal content of 40 wt.% while the fifth anode material of PtRu had a higher content of 60 wt.%. Moreover, in order to show the influence of the metallic content on the fuel cell performance, anode catalysts with 60 wt.% (Pt) and 10wt.% (PtNi) were tested. The operation of the AEMFC was controlled by means of an in-house-made electronic load with PI-controller (i.e. a feedback controller that has proportional and integral action on control error signal) either at constant current (CC) or at constant voltage (CV). The primary objective was to characterize the Coulombic efficiency (CE) based on the exchange of ...

A catalyst consisting of palladium - nickel supported on exfoliated graphene oxide (PdNi/EGO) composite was synthesized. The catalytic activity was tested for ethanol oxidation reaction (EOR) in half-cell using cyclic voltammetry (CV) and subsequently it was used as an anode material in a direct ethanol fuel cell (DEFC). Transmission Electron Microscopy showed the catalyst particles are uniformly dispersed on the surface of graphene oxide with the particle size ranging from 3 to 6 nm. X-ray Photoelectron Spectroscopy analysis of catalysts revealed that the surface consisting of mostly Pd, PdO, Ni(OH)2, and NiOOH. CV and chronoamperometry measurements demonstrated higher electrocatalytic activity and stability for PdNi/EGO in the alkaline medium than the unsupported PdNi and carbon black-supported PdNi (PdNi/C) catalysts. A single cell anion exchange membrane DEFC constructed with a PdNi/EGO anode catalyst showed a maximum power density of 16.6 m Wcm−2 at 50 °C, which is higher than the ...

Volatile fatty acids (VFA) are building blocks for the chemical industry. Sustainable, biological production is constrained by production and recovery costs, including the need for intensive pH correction. Membrane electrolysis has been developed as an in situ extraction technology tailored to the direct recovery of VFA from fermentation while stabilizing acidogenesis without caustic addition. A current applied across an anion exchange membrane reduces the fermentation broth (catholyte, water reduction: H2O + e− → ½ H2 + OH−) and drives carboxylate ions into a clean, concentrated VFA stream (anolyte, water oxidation: H2O → 2e− + 2 H+ + O2). In this study, we fermented thin stillage to generate a mixed VFA extract without chemical pH control. Membrane electrolysis (0.1 A, 3.22 ± 0.60 V) extracted 28 ± 6 % of carboxylates generated per day (on a carbon basis) and completely replaced caustic control of pH, with no impact on the total carboxylate production amount or rate. Hydrogen generated

STUDY OF SPEEK-BASED PROTON EXCHANGE MEMBRANES FOR FUEL CELL APPLICATIONS.POMPES PAR TRANSITIONS MULTIPLES , STUDY OF SPEEK-BASED PROTON EXCHANGE MEMBRANES FOR FUEL CELL APPLICATIONS.POMPES PAR TRANSITIONS MUL... , کتابخانه دیجیتال دانشگاه آزاد اسلامی خوراسگان

TY - JOUR. T1 - Optimal design of baffles locations with interdigitated flow channels of a centimeter-scale proton exchange membrane fuel cell. AU - Jang, Jiin Yuh. AU - Cheng, Chin Hsiang. AU - Huang, Yu Xian. PY - 2010/1/1. Y1 - 2010/1/1. N2 - In the present study, the simplified conjugate-gradient method (SCGM) is combined with commercial CFD code to build an optimizer for designing the baffles locations with interdigitated channels of a centimeter-scale proton exchange membrane fuel cell (PEMFC). Using the optimizer, the locations of the baffles are adjusted toward the maximization of the average current density of the flow field. The approach is developed by using the commercial CFD code as the direct problem solver, which is able to provide the numerical solutions for the three-dimensional mass, momentum and species transport equations as well as to predict the electron conduction and proton migration taking place in a PEMFC. Results show that the optimal design process of the locations of ...

The aim of this work was to develop a porous film structure for an electrode gas diffusion layer (GDL) used for proton exchange membrane fuel cells (PEMFCs). This film was made from a matrix composed of two immiscible polymers filled with a mixture of electrically conductive materials fabricated via a twin-screw extrusion process followed by selective extraction of one of the two polymers. The matrix consisted of low-viscosity polypropylene and polystyrene (PS) and the conductive additives were composed of high specific surface area carbon black and synthetic flake graphite. The conductive blends were first compounded in a corotating twin-screw extruder and subsequently extruded through a flexible film die to obtain a GDL film of around ...

Proton Exchange Membrane Fuel Cells (PEMFC) are promising energy converters, but still suffer from a short life duration. Applying Prognostics and Health M

Tang, H. and Pan, M. and Lu, S. and Lu, J. and Jiang, S.P. 2010. One-step synthesized HPW/meso-silica inorganic proton exchange membranes for fuel cells. Chemical Communications. 46: pp. 4351-4353 ...

In this paper, a fault tolerant control (FTC) strategy for proton exchange membrane (PEM) fuel cells based on the use of virtual actuators and the Takagi- Sugeno (TS) approach is proposed. The overall solution relies on adding a virtual actuator in the control loop to hide the fault from the controller point of view, allowing it to see the same plant as before the fault, such that the stability and some desired performances are preserved. The proposed methodology is based on the use of a reference model, where the resulting nonlinear error model is brought to a Takagi-Sugeno form using a gridding approach. The TS model is suitable for designing a controller using linear matrix inequalities (LMI)-based techniques, such that the resulting closed-loop error system is stable with poles placed in some desired region of the complex plane. Simulation results are used to show the effectiveness of the proposed approach ...

A professor at the University of California, Riverside has won a grant to study quaternary phosphonium-based hydroxide exchange membranes for use in next-generation fuel cells. The award is from the Department of Energys newly formed Advanced Research Projects Agency-Energy (ARPA-E), which funds transformative energy research projects.

A surface segregated bimetallic composition of the formula Ru.sub.1-xIr.sub.x wherein 0.1.ltoreq.x.ltoreq.0.75, wherein a surface of the material has an Ir concentration that is greater than an Ir concentration of the material as a whole is provided. The surface segregated material may be produced by a method including heating a bimetallic composition of the formula Ru.sub.1-xIr.sub.x, wherein 0.1.ltoreq.x.ltoreq.0.75, at a first temperature in a reducing environment, and heating the composition at a second temperature in an oxidizing environment. The surface segregated material may be utilized in electrochemical devices.

A detailed study of the D (a divinyl kenzene polymer substituted with sulfonic acid) and R (D membrane where a teflon polymer is substituted for the divinylbenzene) type ion exchange membranes for manpack fuel cells is presented. The critical current-voltage characteristics of both R and D type of ion exchange membrane electrolyte systems are examined for their capability of meeting the requirements for Army field use. Evaluation of the experimental results shows two main causes for fuel cell break down: (1) the presence of tetra hydrofuran in the fuel causing poisoning of the anode catalyst and eventual cell decay, and (2) ion exchange membrane dry-out due to low current loading and extended periods on open circuit voltage. (Author)(*FUEL CELLS

A novel fluorinated cation exchange membrane containing carboxylic acid groups and sulfonic acid groups, both in the form of a specific pendant structure, the carboxylic acid groups being at least 20% on one surface of the membrane and gradually decreasing toward the innerside of the membrane, which membrane is useful in electrolysis of an aqueous alkali metal halide solution with advantageously stable performance for a long term under more severe operational conditions than those conventionally used. The membrane can be prepared from a novel copolymer of a fluorinated olefin with a novel sulfur containing fluorinated vinylether of the formula: ##STR1## wherein k is 0 or 1, l is an integer of 3 to 5, Z is --S-- or --SO2 -- and R is C1 -C10 alkyl, an aryl, C1 -C10 perfluoroalkyl.

Liquid water management is critical for Proton Exchange Membrane (PEM) fuel cell operation, as excessive humidity can lead to flooding and cell performance degradation. Water is produced in the cathode catalyst layer during the electrochemical reaction. If reactant gas streams become saturated, liquid water forms and must travel through anode and cathode Gas Diffusion Layers (GDLs) to reach flow channels for removal. Understanding the dynamic behavior of the droplet is critical to improve water removal strategies for PEM fuel cells. In this study a 3D, transient, two-phase model based on the Volume of Fluid (VOF) method was developed to study a single droplet in the gas channel. The formation, growth, and breakup of the droplet is tracked numerically and analyzed. The pressure drop across the droplet is monitored over time and compared with theoretical analysis. The droplet size and shape change over time for two different pore sizes are compared. The impact of various gases including air, ...

The Report Global PEMFC (Proton Exchange Membrane Fuel Cells) Market 2015-2019 provides information on pricing, market analysis, shares, forecast, and company profiles for key industry participants. - MarketResearchReports.biz About PEMFC PEMFC are devices that generate electricity through an electrochemical process involving oxidation of electrolytes placed between the anode and the cathode. Fuel cells are generally categorized based on the type of electrolyte used. PEMFC use an acidic water-based polymer membrane with platinum-based electrodes. It operates at low temperatures and caters effectively to dynamic power requirements. The chemical source of PEMFC,…. Read More ...

TY - JOUR. T1 - Improvement of the thermochemical water splitting IS process by an electrochemical cell using a cation exchange membrane. AU - Nomura, Mikihiro. AU - Okuda, Hiroyuki. AU - Kasahara, Seiji. AU - Kubo, Shinji. AU - Onuki, Kaoru. AU - Nakao, Shin-ichi. PY - 2004/6/27. Y1 - 2004/6/27. M3 - Article. JO - Proceedings of 15th World Hydrogen Energy Conference. JF - Proceedings of 15th World Hydrogen Energy Conference. ER - ...

Treatment of oil and gas (O&G) wastewater is a growing practice that increases water resources available for beneficial reuse. Electrodialysis (ED) is an established desalination process with the potential to remove ions from saline produced water (PW), a byproduct of O&G production. However, the current ED literature lacks studies that investigate the fate of organic contaminants during ED treatment using real PW. This work examines ion exchange membrane (IEM) fouling, system performance, and the transport of organic constituents through IEMs during ED treatment of real PW. A bench-scale ED ...

This work highlights the gains of an innovative model-based control approach applied to a proton exchange membrane fuel cell (PEMFC) system, included in a stand-alone hybrid generator. This approach proposes a multivariable setpoint tracking of the PEMFC output power and temperature. The freshness of this approach is based on the combination of a nonlinear model-based predictive control strategy (NMPC) and a global linearizing control (GLC) algorithm. The performance of the proposed control strategy is confirmed thanks to simulations of varying control scenarios. Results show good performance in setpoint tracking, disturbances rejection and robustness against plant/model mismatch in presence of noisy signals. Moreover, for similar setpoint point tracking accuracy, the proposed control strategy appears to be four times faster than a classical multivariable NMPC strategy. According to real-time application objectives, this control strategy appears as a promising option to be implanted in the overall

CO removal from a hydrogen-rich fuel gas for proton exchange membrane (PEM) fuel cell use = CO-Entfernung aus einem wasserstoffreichen Brenngas für eine PEM- ...

The silanol groups on Silica gel surface are sites for adsorption of polar molecules. Alcohols and other polar molecules are easily adsorbed by forming hydrogen bondings with OH groups on silica gel surface. A study on the adsorption of methanol on silica gel was carried out by using NIR spectroscopy in combination with ssecond derivative techniques. Four of the well characterised silica gel samples were used in this study. Each of the silica gel (0.25g) samples with different surface areas and silanol number was pressed into a small disc, placed in a glass vial and the physically adsorbed water molecules from the surface of the silica gel particles were removed by heating the sample to 200 °C under vacuum. The near infrared spectra of the cooled sample was recorded by a Perkin Elmer spectrum one NIR spectrometer equipped with a transflectance accessory and a deuterated triglycine detector at a resolution of 16 cm-1. The glass vial was then opened and a tiny tube filled with methanol was ...

TY - JOUR. T1 - Impedance characterization of high temperature proton exchange membrane fuel cell stack under the influence of carbon monoxide and methanol vapor. AU - Jeppesen, Christian. AU - Polverino, Pierpaolo. AU - Andreasen, Søren Juhl. AU - Araya, Samuel Simon. AU - Sahlin, Simon Lennart. AU - Pianese, Cesare. AU - Kær, Søren Knudsen. PY - 2017/8. Y1 - 2017/8. N2 - This work presents a comprehensive mapping of electrochemical impedance measurements under the influence of CO and methanol vapor contamination of the anode gas in a high temperature proton exchange membrane fuel cell, at varying load current. Electrical equivalent circuit model parameters based on experimental evaluation of electrochemical impedance spectroscopy measurements were used to quantify the changes caused by different contamination levels. The changes are generally in good agreement with what is found in the literature. It is shown that an increased level of CO contamination resulted in an increase in the high ...

... aims at providing comprehensive data on ion exchange membrane caustic

To achieve high temperature operation of proton exchange membrane fuel cells (PEMFC), preferably under ambient pressure, acid-base polymer membranes represent an effective approach. The phosphoric acid-doped polybenzimidazole membrane seems so far the most successful system in the field. It has in recent years motivated extensive research activities with great progress. This treatise is devoted to updating the development, covering polymer synthesis, membrane casting, physicochemical characterizations and fuel cell technologies. To optimize the membrane properties, high molecular weight polymers with synthetically modified or N-substituted structures have been synthesized. Techniques for membrane casting from organic solutions and directly from acid solutions have been developed. Ionic and covalent cross-linking as well as inorganic-organic composites has been explored. Membrane characterizations havebeenmadeincluding spectroscopy,wateruptake and acid doping, thermal and oxidative stability, ...

Proton Exchange Membrane Fuel Cell (PEMFC) uses hydrogen and oxygen for fuel, the whole energy conversion process almost has no negative impact on the environment. The PEM fuel cell stack with the advantages of low-operating temperature, high current density and fast start-up ability is considered to be the next generation of new electric vehicle power. However, due to the limited current output, it is difficult for a single cell to meet the practical application requirements. The actual fuel cell stack is formed by many single cells assembled together. The assembly process is often related to load transfer, material transfer, energy exchange, multi-phase flow, electrochemical reaction and other factors. The performance of MEA (Membrane Electrode Assembly), sealing gaskets and other components will change during the assembly process, which makes the fuel cell stack assembly process more complex. The assembly load of large stack and the inside interface pressure homogeneity significantly affect ...

Catalyst support materials exhibit great influence on the performance and durability of proton exchange membrane (PEM) fuel cells. This minireview article summarises recent developments into carbon nanotube-based support materials for PEM fuel cells, including the membrane electrode assembly (MEA). The advan

In this article, one-phase and three dimensional computational fluid dynamics analysis was utilized to investigate the effect of annular field pattern of proton exchange membrane fuel cells (PEMFC) with different geometry on the performances and species distribution. This computational fluid dynamics code is used for solving the equation in single domain namely the flow field, the mass conservation, the energy conservation, the species transport, and the electric/ionic fields under the assumptions of steady state and non-isothermal. The introduced cell consist of different novelties, such as the way in which reactant gases are supplied to the flow field, the design of the flow field geometry for both anode and cathode and the membrane electrode assembly design and the length and occupied volume decreases up to 40%. Obtained results showed that generation of fuel cells with annular shaped geometry with the same active area and inlet area gave intensively higher current density compared with conventional

In the Experimental Section, paragraph 3, the fifth sentence should read: "The scattering patterns were integrated to generate an I vs q curve, where I is the intensity of scattered X-rays and q is the scattering vector r, q is calculated from scattering angle θ and the wavelength of the X-ray beam λ by the equation q= 4πsin (θ)/λ." The remaining two sentences of that paragraph should be disregarded.. Figure 5 in the original manuscript should be replaced by the new version of Figure 5 shown below. Figure 5 in the published article is the relation between scattering intensity and the scattering angle, rather than q [calculated as q=4πsin (θ)/λ], due to an oversight by the author. The caption remains the same and is included for completeness.. The author apologises for these oversights. ...

The Global Proton Exchange Membrane Fuel Cells Industry 2015 Market Research Report is a professional - Market Research Reports and Industry Analysis

The produced liquid water in cathode catalyst layer (CCL) has significant effect on the operation of proton exchange membrane fuel cell (PEMFC). To investigate this effect, the transport of oxygen in CCL in the presence of immiscible liquid water is studied applying a two-dimensional pore scale model. The CCL was reconstructed as an agglomerated system. To explore the wettability effects, different contact angles were considered at the surface of agglomerates. The effective diffusivity of oxygen was calculated under different contact angles at various saturation levels. The same effective diffusivity was obtained for hydrophilic and hydrophobic domains at lower saturations, however, at saturation above 0.4, hydrophobic domain provided higher effective diffusivity values. The effect of water coverage at reaction surface areas was investigated. The results showed that, at the saturation of 0.4, the hydrophobic domain with the contact angle of 150 has about 2 times more available surface area, due to

Changes that carbon-supported platinum electrocatalysts undergo in a proton exchange membrane fuel cell environment were simulated by ex situ heat treatment of catalyst powder samples at 150 C and 100% relative humidity. In order to study modifications that are introduced to chemistry, morphology, and performance of electrocatalysts, XPS, HREELS and three-electrode rotating disk electrode experiments were performed. Before heat treatment, graphitic content varied by 20% among samples with different types of carbon supports, with distinct differences between bulk and surface compositions within each sample. Following the aging protocol, the bulk and surface chemistry of the samples were similar, with graphite content increasing or remaining constant and Pt-carbide decreasing for all samples. From the correlation of changes in chemical composition and losses in performance of the electrocatalysts, we conclude that relative distribution of Pt particles on graphitic and amorphous carbon is as important for

TABLE-US-00001 TABLE 1 Examples and Comparative Ex. examples 1 2 3 4 5 6 7 8 9 10 Polymerization scale 0.2 1.0 0.2 0.2 0.2 0.2 1.0 1.0 1.0 20.0 (L) Polymerization 1.20 1.22 0.97 1.05 1.05 1.05 1.18 1.12 1.18 1.09 pressure (MPa) Polymerization C6H C6H C6H C6H C4 C6 C6H C6H C6H C6H medium ethane ethane Type of monomer A B C B B B B B B B Addition of monomer All at Continuous Continuous All at All at All at Continuous Continuous Continuous Continuous once once once once TQ value (° C.) 247 252 208 244 201 191 242 230 -- 232 Ion exchange 0.86 0.94 0.97 0.93 0.92 0.95 0.99 1.04 0.95 1.02 capacity (meq/g dry resin) Anion diffusion -- 0.90 -- -- -- -- 1.47 2.83 -- -- coefficient (× 10-8 cm2/sec) Current efficiency -- -- -- -- -- -- -- -- -- 96.4 (%) after one week with usual salt solution Current efficiency -- -- -- -- -- -- -- -- -- 95.8 (%) after ten days with salt solution containing iodine and barium Examples and Comparative Comp. Ex. examples 1 2 3 4 5 Polymerization scale 1.0 1.0 2.5 2.5 2.5 ...

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FuMA-Tech is a leading company for functional membranes and plant technology and is a leading manufacturer of ion exchange membranes for different electrochemical operations. Their modern coating plant produces porous, non-porous and functional membranes with excellent resistance to acids, bases, solvents and oxidation.. ...

Hydrogen Burner Technology (HbT), Rancho Dominguez, Calif., has formed an alliance with Visteon Corp., Dearborn, Mich., to commercialize HbTs hydrogen fuel processors in proton exchange membrane (PEM) fuel-cell systems.

TY - JOUR. T1 - ZIF derived PtNiCo/NC cathode catalyst for proton exchange membrane fuel cell. AU - Hanif, Saadia. AU - Shi, Xuan. AU - Iqbal, Naseem. AU - Noor, Tayyaba. AU - Anwar, Rehan. AU - Kannan, A. M.. PY - 2019/12/5. Y1 - 2019/12/5. N2 - High performance cathode catalysts with minimum platinum amount for the electrocatalyzed oxygen reduction reaction (ORR) in PEMFCs remain as a significant challenge for commercial application. Zeolitic Imidazolate Framework (ZIF) based catalyst can provide void 3D framework of N-doped nano-porous carbon for promising ORR activity. Here we report a bimetallic pyrolyzed NiCo-ZIF supported fine Pt/Pt alloy electrocatalyst for ORR. After pyrolysis, nano-porous carbon is obtained with well dispersed Pt/Pt alloy nanoparticles (˜ 3 nm). This catalyst shows superior performance and stability in acidic medium against the commercial catalyst comprising of Pt/C. In a single cell PEMFC, high peak power density value of 1067 mW. cm−2 is attained at 70 °C by ...

Asia-Pacific Ion Exchange Membrane of All-Vanadium Redox Flow Battery Market by Manufacturers, Regions, Type and Application, Forecast to 2022 is a market research report available at US $4480 for a Single User PDF License from RnR Market Research Reports Library.

Sustained potential oscillations are experimentally observed in a proton exchange membrane fuel cell with PtRu as anode catalyst and with H2/108ppm CO as the anode feed when operating under a constant current density mode. These oscillations appear at fuel-cell temperatures below 70°C. A threshold value exists for both the current density and the anode flow rate at a given fuel-cell temperature for their onset. The temperature dependence of the oscillation period shows an apparent activation energy around 60 kJ/mol. The potential oscillations are believed to be due to the coupling of anode electro-oxidation of H2 and CO on the PtRu catalyst surface, on which OHad is formed more readily, i.e., at lower overpotentials. A simple kinetic model is provided that can reproduce the observed oscillatory phenomenon both qualitatively and quantitatively.

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The piling of anion and cation ion exchange membranes can provide a kind of pseudo-charge mosaic membranes and that can be practically used in various industrial applications, and is worth of further detailed studies.

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The teams demonstration battery features two glass tubes packed with ion exchange membranes and a blade of solution-soaked grass with both connected together using a thin wire. That wire is where the electrons flow, moving from one end to the other while slowly dissipating energy while a pair of metal tips on the other end of the glass tubes are where the ion current flows.. To prove that ionic flow, the researchers connected the glass tubes at the ends of a lithium-soaked cotton string with a deposition of blue-dyed copper ions placed in the middle. When the current started flowing, that deposition began moving toward the negative charged glass pole, thus proving the ionic current.. The team has high hopes for their new battery and envision them being used for a number of applications, including the micro-manipulation of neural activities to prevent or treat people with Alzheimers disease and depression. They also plan to diversify the types of ion batteries they can produce by using ...

TY - JOUR. T1 - Pre-oxidized and nitrided stainless steel alloy foil for proton exchange membrane fuel cell bipolar plates. Part 2. T2 - Single-cell fuel cell evaluation of stamped plates. AU - Toops, Todd J.. AU - Brady, Michael P.. AU - Tortorelli, Peter F.. AU - Pihl, Josh A.. AU - Estevez, Francisco. AU - Connors, Daniel. AU - Garzon, Fernando. AU - Rockward, Tommy. AU - Gervasio, Don. AU - Mylan, William. AU - Kosaraju, Sree Harsha. PY - 2010/9/1. Y1 - 2010/9/1. N2 - Thermal (gas) nitridation of stainless steel alloys can yield low interfacial contact resistance (ICR), electrically conductive and corrosion-resistant nitride containing surface layers (Cr2N, CrN, TiN, V2N, VN, etc.) of interest for fuel cells, batteries, and sensors. This paper presents results of proton exchange membrane (PEM) single-cell fuel cell studies of stamped and pre-oxidized/nitrided developmental Fe-20Cr-4V weight percent (wt.%) and commercial type 2205 stainless steel alloy foils. The single-cell fuel cell ...

Title:L-Pyrrolidine-2-Carboxylic Acid-4-Hydrogen Sulfate (Supported on Silica Gel) as a New and Efficient Catalyst for Acylation of Alcohols, Phenols and Amines Under Solvent-Free Conditions. VOLUME: 10 ISSUE: 5. Author(s):Maryam Hajjami, Arash Ghorbani-Choghamarani and Zahra Khani. Affiliation:Department of Chemistry, Faculty of Science, Ilam University, P.O. Box 69315516, Ilam, Iran.. Keywords:Acylation, L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate, Acetic anhydride, Alcohol, Phenol, Amine.. Abstract:In the present work, L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate, supported on silica gel was prepared and characterized by Mass spectroscopy, 1H NMR, 13CNMR, FT IR and elemental analysis (CHN) methods. This heterogenized catalyst can be used as an efficient catalyst for the acylation of alcohols, phenols, and amines with acetic anhydride under mild and solvent-free conditions. Simple work-up, stability of the catalyst, nontoxicity and good to high yields are the advantages of this ...

MAHRENI, Mahreni and MOHAMAD, Abu Bakar and KADHUM, Abdul Amir Hasan. and Daud, Wan Ramli Wan (2010) NANOCOMPOSITE ELECTROLYTE MEMBRANE FOR MODERATE TEMPERATURE AND LOW RELATIVE HUMIDITY HYDROGEN PROTON EXCHANGE MEMBRANE FUEL CELL (HPEMFC) APPLICATlON. Departement Of Chemical Engineering, ITB. ...

The report documents the study on a hydrogen proton exchange membrane (PEM) fuel cell powered unmanned aerial vehicle (UAV) named Kenyalang-1. Common aircraft utilize internal combustion engines (ICE) as main power source for the propulsion system. However, ICE imposes negative impact towards the environment due to the pollution produced through carbon emission, initiating green house effect, global warming, and health problems. Researchers have started to develop interest on the possibilities of using alternative energies to replace ICE aircraft propulsion system. Due to the relatively new nature of the technology, there is a need for a research on the development of a ftiel cell electrical propulsion system. The objectives of this project are to design and to develop a fuel cell propulsion system that operates using a 500 W hydrogen PEM fuel cell as the main power generator for a UAV. The research is important to determine the capability of the propulsion system to power a custom designed and ...

Publishers Accepted Manuscript: Study of acetylene poisoning of Pt cathode on proton exchange membrane fuel cell spatial performance using a segmented cell system ...

Master of Science thesis from the Univesiti Sains Malaysia, December 1975. ❧ Abstract: The adsorption of benzene on silica gel samples with different stages of purification has been investigated by both sorption and dielectric measurements. ❧ The shape of the sorption isotherms obtained from all the samples is found to belong to Type IV of the BET classification. From the sorption data, various analyses, such as the BET method, pore size distribution, t-method and the like, have been carried out. The results indicate that prolonged purification of a commercial silica gel by treatment with acids, followed by washing with distilled water, not only removes impurities but also results in a drastic change in the pore structure of the gel. These changes involve a sharp decrease in the pore volume and surface area of the impure gel, due to removal of the majority of the narrow pores, a wider and more uniform distribution of pore sizes and an alteration of the pore shape. ❧ The adsorption of ...

A central venous catheter includes coolant supply and return lumens which communicate coolant to and from first and second heat exchange membranes arranged along the distal segment of the catheter. The coolant in the heat exchange membranes removes heat from the patient. Additional lumens are provided for conventional central venous catheter uses.

Silicon micro-hole arrays (Si-MHA) were fabricated as a gas diffusion layer (GDL) in a micro fuel cell using the micro-electro-mechanical-systems (MEMS) fabrication technique. The resistance temperature detector (RTD) sensor was integrated with the GDL on a bipolar plate to measure the temperature inside the fuel cell. Experimental results demonstrate that temperature was generally linearly related to resistance and that accuracy and sensitivity were within 0.5 °C and 1.68×10-3/°C, respectively. The best experimental performance was 9.37 mW/cm2 at an H2/O2 dry gas flow rate of 30/30 SCCM. Fuel cell temperature during operation was 27 °C, as measured using thermocouples in contact with the backside of the electrode. Fuel cell operating temperature measured in situ was 30.5 °C.

Between two juxtaposed similar ion exchange membranes (AEMs or CEMs), an ion depletion zone and ion enrichment zone are generated under an electric field. As cations are selectively transferred through the CEMs, for example, anions are relocated in order to achieve electro-neutrality, resulting in the concentration drop (increase) in ion depletion (enrichment) zone. The use of a sacrificial metal anode allows electrocoagulation (EC) concurrently with ICP thereby permitting concentration of both ionic and non-ionic impurities to occur at the same time within the same cell or device.

Plug Power signed an agreement with 3M to supply the fuel cell manufacturer with membrane electrode assemblies. The assemblies are used in making proton exchange membrane fuel cell stacks that Plug Power makes in Latham and in Spokane, Wash. The fuel cells are used mostly in fork lift trucks, although the company is expanding to other types of electric vehicles. - Larry Rulison

The Fuel Cell Power System Market (By Product Type - Solid Oxide Fuel Cells, Proton Exchange Membrane Fuel Cell, Molten Carbonate Fuel Cell, Phosphoric...

DMFC is a subcategory of the proton exchange membrane fuel cell (PEMFC) that uses methanol as the fuel. It was invented and developed in 1990. A DMFC anode can draw hydrogen directly from liquid methanol. This action eliminates the need to have a fuel reformer, allowing the direct use of pure methanol as a fuel. Methanol provides several advantages as it is convenient to handle and easily available. Publisher’s analysts forecast the global DMFC market to grow at a CAGR of 40.... ...

TY - JOUR. T1 - Phosphoric acid doped imidazolium polysulfone membranes for high temperature proton exchange membrane fuel cells. AU - Yang,Jingshuai. AU - Li,Qingfeng. AU - Jensen,Jens Oluf. AU - Pan,Chao. AU - Cleemann,Lars Nilausen. AU - Bjerrum,Niels J.. AU - He,Ronghuan. PY - 2012. Y1 - 2012. N2 - A novel acid-base polymer membrane is prepared by doping of imidazolium polysulfone with phosphoric acid for high temperature proton exchange membrane fuel cells. Polysulfone is first chloromethylated, followed by functionalization of the chloromethylated polysulfone with alkyl imidazoles i.e. methyl (MePSU), ethyl (EtPSU) and butyl (BuPSU) imidazoliums, as revealed by 1H NMR spectra. The imidazolium polysulfone membranes are then doped with phosphoric acid and used as a proton exchange membrane electrolyte in fuel cells. An acid doping level of about 10-11mol H3PO4 per mole of the imidazolium group is achieved in 85wt% H3PO4 at room temperature. The membranes exhibit a proton conductivity of ...

The performance of thin carboxylated cellulose nanofiber-based (CNF) membranes as proton exchange membranes in fuel cells has been measured in situ as a function of CNF surface charge density (600 and 1550 mu mol g(-1)), counterion (H+ or Na+), membrane thickness and fuel cell relative humidity (RH 55 to 95%). The structural evolution of the membranes as a function of RH, as measured by Small Angle X-ray Scattering, shows that water channels are formed only above 75% RH. The amount of absorbed water was shown to depend on the membrane surface charge and counter ions (H+ or Na+). The high affinity of CNF for water and the high aspect ratio of the nanofibers, together with a well-defined and homogenous membrane structure, ensures a proton conductivity exceeding 1 mS cm(-1) at 30 degrees C between 65 and 95% RH. This is two orders of magnitude larger than previously reported values for cellulose materials and only one order of magnitude lower than Nafion 212. Moreover, the CNF membranes are ...

Gas diffusion electrodes (GDEs) prepared by a novel automatic catalyst spraying under irradiation (ACSUI) technique are investigated for improving the performance of phosphoric acid (PA)-doped polybenzimidazole (PBI) high temperature proton exchange membrane fuel cell (PEMFC). The physical properties of the GDEs are characterized by pore size distribution and scanning electron microscopy (SEM). The electrochemical properties of the membrane electrode assembly (MEA) with the GDEs are evaluated and analyzed by polarization curve, cyclic voltammetry (CV) and electrochemistry impedance spectroscopy (EIS). Effects of PTFE binder content, PA impregnation and heat treatment on the GDEs are investigated to determine the optimum performance of the single cell. At ambient pressure and 160 o C, the maximum power density can reach 0.61 W cm-2, and the current density at 0.6 V is up to 0.38 A cm-2, with H /air and a platinum loading of 0.5 mg cm-2 on both electrodes. The MEA with the GDEs shows good ...

In this study, immobilized COX-2 was successfully constructed through glutaraldehyde-mediated covalent coupling on functional silica gel microspheres. The optimum conditions, properties, and morphological characteristics of the immobilized COX-2 were investigated. The optimal immobilization process was as follows: about 0.02 g of aminated silica gel microspheres was activated by 0.25% GA solution for 6 h and mixed with 5 U of free recombinant COX-2 solution. Then, the mixture was shaken for 8 h at 20 °C. Results showed that the immobilized COX-2 produced by this method exhibited excellent biocatalytic activity, equivalent to that of free COX-2 under the test conditions employed. The best biocatalytic activity of immobilized COX-2 appeared at pH 8.0 and still maintained at about 84% (RSD < 7.39%, n = 3) at pH 10.0. For temperature tolerance, immobilized COX-2 exhibited its maximum biocatalytic activity at 40 °C and about 68% (RSD < 6.99%, n = 3) of the activity was maintained at 60 °C. The

TY - JOUR. T1 - Experimental analysis of a dimensionless number in the cathode channels of a polymer electrolyte membrane fuel cell with different head losses. AU - Han, S. H.. AU - Kim, K. R.. AU - Ahn, D. K.. AU - Choi, Y. D.. PY - 2010/1/1. Y1 - 2010/1/1. N2 - This study investigates the effects of stoichiometry, humidity, cell temperature, and pressure on the performance and the flooding of the proton exchange membrane fuel cell. Values of stoichiometry are 1.5, 2.0, and 2.5 at cell temperatures of 50, 55, and 60°C, respectively. This study shows that the dimensionless flooding value (FV) is a function of the stoichiometry, humidity, temperature, and pressure. The FV is calculated by using the measured values of temperature, humidity, pressure, and flowrate of the cathode. The effect of the dimensionless number on the flooding of the cathode in the proton exchange membrane fuel cell is analysed in this study. The effects of air stoichiometry, cell temperature, and air humidity are also ...

EFC Fuel Cell Hardware includes a conditioned MEA (Membrane Electrode Assembly) installed inside the hardware utilizing ElectroChems proprietary technology for leak-tight performance.. ElectroChems EFC Fuel Cell Hardware is used by many of our global customers as the standard they utilize in the development of their membrane electrode assemblies (MEA). They are completely assembled fuel cells for any researcher to utilize for the understanding the basic operation of a fuel cell. It helps the researcher to understand the effect of gas flow rate, pressure, and its impact on performance. The EFC fuel cell hardware is quality control tested prior to shipment - and is sent with a performance curve based on that testing.. ...

Catalysts play an essential role in nearly every chemical production process. Platinum supported on high surface area carbon substrates (Pt/C) is one of the promising candidates as an electrocatalyst in low temperature polymer electrolyte fuel cells. Developing the activity of the Pt/C catalyst with narrow Pt particle size distribution and good dispersion has been a main concern in current research.. In this study, the main objective was the development and characterization of inexpensive and effective nanophase Pt/C electrocatalysts. A set of modified Pt/C electrocatalysts with high electrochemical activity and low loading of noble metal was prepared by the impregnation-reduction method in this research. The four home-made catalysts synthesized by different treatments conditions were characterized by several techniques such as EDS, TEM, XRD, AAS, TGA, BET and CV.. Pt electrocatalysts supported on acid treatment Vulcan XC-72 electrocatalysts were produced successfully. The results showed that Pt ...

Cations such as Cu2+, Cr3+ and Hg+ can be separated on silica gel thin layer Chromatographic plates. The developing solution contains 0.02 M EDTA at pH 2.5. For visualization, the plate was pretreated with ethidium bromide, a strong fluorescer. Quenching of the red fluorescence can be observed visually even down to the 0.1 nmole range per spot.