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Typical microcombustion-based power devices entail the use of catalyst to sustain combustion in less than millimeter scale channels. This work explores the use of several other candidate fuels for ~8 nm diameter Pt particle catalyzed combustion within 800 μm channel width cordierite substrates. The results demonstrate while commercial hydrocarbon fuels such as methane, propane, butane, and ethanol can be used to sustain catalytic combustion, room temperature ignition was only observed using methanol-air mixtures. Fuels, other than methanol, required preheating at temperatures >200°C, yet repeated catalytic cycling similar to methanol-air mixtures was demonstrated. Subsequently, a new reactor design was investigated to couple with thermoelectric generators. The modified reactor design enabled ignition of methanol-air mixtures at room temperature with the ability to achieve repeat catalytic cycles. Preliminary performance studies achieved a maximum temperature differenceΔTof 55°C with a flow rate of 800 mL/min. While the temperature difference indicates a respectable potential for power generation, reduced exhaust temperature and improved thermal management could significantly enhance the eventual device performance.

Catalytic combustion is a practical approach to sustain and manage combustion in microreactors. Previous work has demonstrated room-temperature ignition and size-dependent properties of platinum nanoparticles as they related to catalytic combustion of hydrocarbons. This work investigates the use of platinum nanoparticle coatings to combust a stochiometric methanol–air mixture. Platinum nanoparticles with dp = 8 nm were used to coat cordierite substrates with 800 μm wide square channels. Room-temperature ignition of the methanol–air mixture and repeated catalytic cycling were successfully achieved with operational temperatures ranging from 250 to 850 °C. The catalysis reaction was controlled by altering fuel–air flow rates and catalyst mass loading. A nanoparticle stability study indicated a minimal effect of sintering on the combustion behavior and vice versa with repeated catalytic cycling. A product gas analysis indicated that overall methanol conversion rates of up to 60% were achieved with the current...