A hydrogen purification and storage system using CO adsorbent and metal hydride

The CO Selective Adsorbent and Metal Hydride Intermediate Buffer (COA-MIB) method has been proposed as a hydrogen production/supply system with reformer. First, this method thoroughly eliminates carbon monoxide using an adsorption material that strongly selects carbon monoxide, and second it introduces a mixed gas to a metal hydride that purifies and stores hydrogen. A 100 NL/h laboratory scale apparatus was operated in daily start and stop operations for 1000 cycles for a total of 1500 h with quite good efficiency. The metal hydride used in this apparatus was an AB5-type whose hydrogen equilibrium pressure was adjusted to be 0.1 MPa at 25 C. As a result of the basic performance evaluation, we have experimentally verified that pure hydrogen can be produced from methanol reforming gas for 1000 cycles on a daily start/stop operation basis and a high hydrogen recovery rate of over 89% can be achieved. 3 N m³/h Bench scale apparatus was also operated with same mode for 100 cycles for a total of 150 h and shows almost the same performance. The new method enables us to minimize emissions of carbon dioxide by using compact and highly efficient fuel cells as a part of the smart community technologies.