Rare earth-nickel alloy for hydrogen compression

Abstract The equilibrium pressure of the reaction between hydrogen and hydrogen storage alloys varies with temperature. A metal hydride compressor without moving parts was made to produce ultrapure high presure hydrogen. In this paper, the principle of hydride hydrogen compression alloy were studied in detail. A successful hydrogen compression alloy is reported. It absorbs industrial hydrogen (98% purity) at 288 K and 1.6 MPa and releases ultrapure hydrogen (99.9999% purity) at 368 K and 10 MPa. Finally, the relation between compression ratio, thermal efficiency of compression and heat of hydride reaction is also discussed.