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PEM reactor

Fig. 9. Single-cell PEM reactor used to destroy organic waste streams. (Adapted from [39]). Fig. 9. Single-cell PEM reactor used to destroy organic waste streams. (Adapted from [39]).
Tatapudi and Fenton [69] explored the synthesis of ozone in a proton exchange membrane (PEM) electrochemical flow reactor as part of an overall scheme to study the paired synthesis of ozone and hydrogen peroxide in the same PEM reactor. A mixture of commercially available lead dioxide powder and Teflon , deposited on a Nafion 117 membrane, was used as the anode. Current efficiencies ranged from 2.5% at an applied potential of 3.0 V to 5.5% at 4.0 V. The low current efficiencies were attributed to inefficient reactor design. A decrease in ozone concentrations, observed at higher applied potentials (> 4.0 V) was attributed to the disintegration of lead dioxide at high anodic potentials. [Pg.385]

The Kolbe electrolysis of acetate to ethane and carbon dioxide was modeled for a parallel-plate reactor. Three zones were considered in the model a turbulent bulk region, and a thin diffusion layer at each electrode [184b]. The same authors describe the electrolysis of gaseous acetic acid in a polymer electrolyte membrane (PEM) reactor. Platinized... [Pg.934]

A polymer electrolyte membrane (PEM) reactor is described by Hicks and Fedkiw [2.454] for use during Kolbe electrolysis, which involves the anodic oxidation of an alkyl carboxylic acid, and its subsequent decarboxylation and coupling to produce a dimer. [Pg.79]

Fig. 4. Electrochemical reactor and water circulation Fig. 5. Plot of cell voltage vs duration of PEM reactor... Fig. 4. Electrochemical reactor and water circulation Fig. 5. Plot of cell voltage vs duration of PEM reactor...
The CiijCe, r02 v nanostructuied catalyst prepared by the sol-gel method is a very efficient and selective CO oxidation catalyst even under the highly reducing conditions which are present in a PrOX reactor. It is energy efficient toward the PEM fuel cell technology, because it oxidizes CO... [Pg.222]

Another application of carbon and carbon hybrids is their use as electrode material in proton exchange membrane (PEM) electrochemical flow reactor for the production of hydrogen peroxide (H202). [Pg.365]

Due to the operating requirements of PEM stack technology, shift reactors and a carbon monoxide removal step are required to produce reformate of sufficient quality. Similarly, the stack operating temperature and its humidity requirements require a water management system as well as radiators for heat rejection. Some developers are developing pressurized systems to the benefit from higher reactant partial pressures on both anode and cathode. Fuel processing for PEM APU systems is identical to that needed in residential power or propulsion applications. [Pg.47]

Arthur D. Little has carried out cost structure studies for a variety of fuel cell technologies for a wide range of applications, including SOFC tubular, planar and PEM technologies. Because phenomena at many levels of abstraction have a significant impact on performance and cost, they have developed a multi-level system performance and cost modeling approach (see Figure 1-15). At the most elementary level, it includes fundamental chemical reachon/reactor models for the fuel processor and fuel cell as one-dimensional systems. [Pg.48]

As with the other reactor configurations, vaporizers, heat exchangers, and a heat source are also needed for microreactors.Unless the hydrogen is 99.999% pure, the PEM fuel cell typically will utilize 70—80% of the diluted hydrogen fed to it. The unreacted hydrogen from the fuel cell anode, augmented with additional fuel as needed, can be used as fuel for the combustor. The use of anode off-gas requires special controls for transient operating conditions for example, a mechanism is needed to... [Pg.532]

PEM fuel cells operate at relatively low temperatures, around 80°C. Low temperature operation allows them to start quickly (less warm-up time) and results in less wear on system components, resulting in better durability. However, they require that a noble-metal catalyst (typically platinum) be used to separate the hydrogen s electrons and protons, adding to system cost. The platinum catalyst is also extremely sensitive to CO poisoning, making it necessary to employ an additional reactor to reduce CO in the fuel gas if the hydrogen is derived from an alcohol or hydrocarbon fuel. This also adds cost. Developers are currently exploring platinum/ruthenium catalysts that are more resistant to CO. [Pg.25]

The Institute of Chemical Engineering and High Temperature Chemical Processes (ICE/HT) works on design, construction and testing of PEM components, electrochemical reactions/reactors, electrocatalysts for PEMs, hydrogen production by catalytic processes and water splitting. [Pg.139]

P. L., A carbon monoxide PROX reactor for PEM fuel cell automotive application, Int. J. Hydrogen Energy 2001, 26, 763-775. [Pg.404]

P P Po PCHE PCR PCS PDF PDMS Pe PEM PEMFC PET pH Power output Pressure Pressure drop of one SAR step Printed circuit heat-exchanger Printed circuit reactor Process control system Probability density function Poly-dimethylsiloxane Peclet-number Proton exchange membrane Proton exchange membrane fuel cell Poly-ethylene terephthalate Potentia Hydrogenii (measure for acid and base strength)... [Pg.685]

The UMR process was studied in a pilot scale experimental system. A simplified schematic of the pilot scale system is shown in Figure 5. The pilot scale system consists of two packed bed reactors. The system was designed to produce 100 standard liters per minute of hydrogen, which is sufficient to generate 10 kW of electricity using a PEM fuel cell. [Pg.39]


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