Experimental study of performance enhancement strategies for hydrogen production-purification systems in packed-bed reactors under power fluctuations

Methanol reforming for hydrogen production and purification is a key technology in current fuel cell hydrogen source systems. The packed-bed reactor has a simple structure and is widely used, yet it has disadvantages such as slow dynamic response and limited heat and mass transfer. In this paper, an experimental approach is used to simulate the reaction characteristics of the packed bed during power fluctuation and start-up phase. It is found that the combined catalysts are the best in terms of both economical and purification effects, especially the precious metal combined copper-based catalysts. Meanwhile, the methanol conversion rate can seriously affect CO-PROX during the fuel cell start-up phase, and the use of combined catalysts can mitigate the impact of power fluctuation on the system and reduce the CO concentration. The combination of catalysts in such a way that the noble metal should be ensured in the front section, the optimal reaction temperature of copper-based combination noble metal-based catalysts is explored, with reforming temperature of 200 °C and CO-PROX temperature of 180–200 °C, and optimal O₂/CO ratio between 0.5 and 1.5, when methanol conversion reaches more than 70%, CO concentration as low as 0.42% and hydrogen concentration higher than 40%.