V. Cominos

A Methanol Steam Micro-Reformer for Low Power Fuel Cell Applications

Abstract A micro-reformer was fabricated and its performance investigated using copper-zinc catalysts with differing compositions and loadings at various operating conditions. A catalyst with 3:1 copper-to-zinc ratio and 8 wt% loading produced enough hydrogen to power a 28W PEM fuel cell when using a third of the reformers volume (8 cm3) and assuming 64% fuel cell efficiency. Methanol conversion was 65% while hydrogen content in the off-gas was 45% at a temperature of 275°C and residence time of 0.11s. Carbon monoxide levels were approximately 1.45%. Higher methanol conversions (80%) and hydrogen content in the off-gas (50%) were achieved by a second catalyst with 16 wt% at 290°C while utilizing the entire reformer volume. Hydrogen yield and selectivity were high (78 and 98% respectively). Extrapolating from present results, the maximum power output possible to be achieved by this device is 84 W.

Microstructured fuel processors for fuel-cell applications

Microstructured reactors are being developed at IMM for the processing of various fuels to provide hydrogen for mobile and portable fuel-cell systems. The key feature of the systems is the integrated-plate heat-exchanger technology, which allows for thermal integration of several functions in a single device. For example, steam reforming may be coupled with exothermic reactions in separate flow-paths of a heat exchanger. Catalyst coatings are also under development for numerous reactions, such as propane steam reforming, methanol steam reforming, catalytic combustion, water-gas shift, and preferential oxidation of carbon monoxide. These catalysts are being investigated in specially developed testing reactors. Reactors and complete fuel processors are being tested up to 5 kW power output of the corresponding fuel cell.

MiRTH-e: Micro reactor technology for hydrogen and electricity

Research groups of six companies, institutes and universities have joint forces in a European Community funded project, to develop a miniaturized, low-power fuel processor for the conversion of methanol into clean hydrogen for use in a proton exchange membrane (PEM) fuel cell. The integrated unit will provide a portable power source and is an alternative for battery packs or hydrogen storage in metal hydrides. In the realization of this small-scale fuel processor, microreactor technology will play a key role. Based upon a so-called pinch analysis, a conceptual design of the fuel processor is made, consisting of three combined microreactors/heat exchangers.