Evan O. Jones

Miniature Fuel Processors for Portable Fuel Cell Power Supplies

Miniature and micro-scale fuel processors are discussed. The enabling technologies for these devices are the novel catalysts and the micro-technology-based designs. The novel catalyst allows for methanol reforming at high gas hourly space velocities of 50,000 hr-1 or higher, while maintaining a carbon monoxide levels at 1% or less. The micro-technology-based designs enable the devices to be extremely compact and lightweight. The miniature fuel processors can nominally provide between 25-50 watts equivalent of hydrogen which is ample for soldier or personal portable power supplies. The integrated processors have a volume less than 50 cm3, a mass less than 150 grams, and thermal efficiencies of up to 83%. With reasonable assumptions on fuel cell efficiencies, anode gas and water management, parasitic power loss, etc., the energy density was estimated at 1700 Whr/kg. The miniature processors have been demonstrated with a carbon monoxide clean-up method and a fuel cell stack. The micro-scale fuel processors have been designed to provide up to 0.3 watt equivalent of power with efficiencies over 20%. They have a volume of less than 0.25 cm3 and a mass of less than 1 gram.

High-Efficiency Microscale Power Using a Fuel Processor and Fuel Cell

A microscale power device, composed of a fuel processor and a fuel cell, is described, and results of testing conducted with the fuel reformer are presented. The microscale fuel reformer strips hydrogen from a hydrocarbon fuel, such as methanol, and the hydrogen-rich stream can then be fed to a fuel cell to generate electrical power. In the tests discussed here, the fuel reformer, utilizing methanol, was able to provide up to 100 mWe of hydrogen at an efficiency of up to 4.8%. The device was able to operate independent of any additional external heating, even during start-up.

Separation of strontium-90 from Hanford high-level radioactive waste

Abstract Current guidelines for disposing of high-level radioactive wastes stored in underground tanks at the U.S. Department of Energys Hanford Site call for vitrifying high-level waste (HLW) in borosilicate glass and burying the glass canisters in a deep geologic repository. Disposition of the low-level waste (LLW) is yet to be determined, but it will likely be immobilized in a glass matrix and disposed of on site. To lower the radiological risk associated with the LLW form, methods are being developed to separate 90Sr from the bulk waste material so this isotope can be routed to the HLW stream. A solvent extraction method is being investigated to separate 90Sr from acid-dissolved Hanford tank wastes. Results of experiments with actual tank waste indicate that this method can be used to achieve separation of 90Sr from the bulk waste components. Greater than 99% of the 90Sr was removed from an acidic dissolved sludge solution by extraction with di-t-butylcyclohexano-18-crown-6 in 1-octanol (the SREX pro...

Sub-watt Power Using an Integrated Fuel Processor and Fuel Cell

A sub-watt power system is being developed as an alternative to conventional battery technology to better meet energy and power densities needed for operating wireless electronic devices, such as microsensors and microelectromechanical systems. This system integrates a microscale fuel processor, which produces a hydrogen-rich stream from liquid fuels, such as methanol and butane, and a microscale fuel cell, which uses the hydrogen as fuel to produce electric power. Battelle, Pacific Northwest Division and Case Western Reserve University are developing and demonstrating this technology for the Defense Advanced Research Projects Agency. This paper describes work being performed by Battelle on the fuel processor, in particular, catalyst and reactor design and testing.