Portable power production from methanol in an integrated thermoeletric/microreactor system

Catalytic self-ignition of methanol over platinum supported on anodized alumina in a microburner is demonstrated. The effects of air flow rate and air/methanol ratio on the system start-up time and steady state temperature have been studied. The air flow rate strongly affects the system start-up time. However, at the same flow rate, the start-up time is not affected by the air/methanol ratio over the range studied. Computational fluid dynamics simulations confirm these experimental findings. It is proposed that high flow rates and relatively lower fuel content can lead to attaining steady state faster with minimal fuel utilization. Transient axial temperature profiles showed that the hot spot of the reaction started at the inlet of the burner and did not shift downstream with time under most reaction conditions. The burner effective thermal conductivity was increased using copper thermal spreaders on the burner outer walls, allowing for thermally uniform walls. The uniform temperature profile allowed for optimal integration of the microburner with a thermoelectric device. The integrated microburner/thermoelectric device was shown to self-start from room temperature. The maximum power generated with the thermoelectric was 0.65 W and the maximum thermal efficiency was 1.1%.