New Material Needs for Hydrocarbon Fuel Processing: Generating Hydrogen for the PEM Fuel Cell

Abstract

▪ Abstract The hydrogen economy is fast approaching as petroleum reserves are rapidly consumed. The fuel cell promises to deliver clean and efficient power by combining hydrogen and oxygen in a simple electrochemical device that directly converts chemical energy to electrical energy. Hydrogen, the most plentiful element available, can be extracted from water by electrolysis. One can imagine capturing energy from the sun and wind and/or from the depths of the earth to provide the necessary power for electrolysis. Alternative energy sources such as these are the promise for the future, but for now they are not feasible for power needs across the globe. A transitional solution is required to convert certain hydrocarbon fuels to hydrogen. These fuels must be available through existing infrastructures such as the natural gas pipeline. The present review discusses the catalyst and adsorbent technologies under development for the extraction of hydrogen from natural gas to meet the requirements for the proton exchange membrane (PEM) fuel cell. The primary market is for residential applications, where pipeline natural gas will be the source of H2 used to power the home. Other applications including the reforming of methanol for portable power applications such as laptop computers, cellular phones, and personnel digital equipment are also discussed. Processing natural gas containing sulfur requires many materials, for example, adsorbents for desulfurization, and heterogeneous catalysts for reforming (either autothermal or steam reforming) water gas shift, preferential oxidation of CO, and anode tail gas combustion. All these technologies are discussed for natural gas and to a limited extent for reforming methanol.

Oxidation enthalpies for reduction of ceria surfaces

“…Ceria-based materials have been used for many years in automotive emissions control for Oxygen-Storage Capacitance (OSC) [1][2][3] and are finding many new applications as supports for water-gas-shift catalysts [4][5][6][7][8][9][10][11][12], supports for reforming catalysts [13,14], and as hydrocarbon oxidation catalysts in diesel emissions [15,16]. In all of these applications, it is likely that the ability of cerium to cycle between Ce +3 and Ce +4 is crucial.…”

High pressure autothermal reforming in low oxygen environments

“…Therefore the experimental results wou ld be expected to include more CH 4 and less CO per mole of CH 4 consumed . A similar H2 yield is possible depending on how much H2 is produced by the WGS shift.…”

H 2 Production and Fuel Cells

“…106 Technologies including heterogeneous catalysts for the water gas shift reaction, the reforming of methanol (either autothermal or steam reforming), the preferential oxidation of CO, and anode tail gas combustion were discussed in detail in this article. 106 The rapid development in recent years of the PEM fuel cell technology has stimulated research in all areas of fuel processor catalysts for hydrogen generation. The principal aim is to develop more active catalytic systems that allow for the reduction in size and increase the efficiency of fuel processors.…”

“…A transitional solution is required to convert certain hydrocarbon fuels to hydrogen. 9 Renewable energy sources such as hydraulic, solar, wind, geothermal, wave and solid waste energy can be used to generate hydrogen from hydrocarbons and/or water. The use of natural gas represents a partial solution because of its high content of hydrogen.…”