Hydrogen absorption of slurry system composed of different MgNi alloy and benzene
(College of Materials Science and Chemistry Engineering, Zhejiang University,
Hangzhou 310027, China)
Hangzhou 310027, China)
Abstract: The hydrogen absorption amount and kinetics of the slurry formed by suspending the MgNi alloy powder in liquid benzene were studied. It is discovered that hydrogen is absorbed by both the solid phase(alloy) and liquid phase(C6H6) and the hydrogen absorption rate varies with the temperature and the content of the Mg-Ni in the slurry. Most hydrogen absorption curves of the slurry fall into two regions, in which the mechanism of hydriding reaction in the slurry system is different. In the former region, the hydriding of the alloy proceeds with hydrogen diffusing through C6H6. The part in the second region is the outcome of the hydrogenation of C6H6. At 548K and under the hydrogen pressure of 4.5MPa the saturation capacity for the slurry of 80% C6H6(mass fraction)+20% MgNi(mass fraction) is 5.9% (mass fraction) hydrogen, which is 97% of the theoretic capacity of the slurry system. The hydride of the alloy MgNi, which is only the hydride of Mg2Ni phase, Mg2NiH4, is an efficient catalyst for the hydrogenation of C6H6 into C6H12(C6H6+3H2→C6H12) in the slurry system.
Key words: MgNi alloy; slurry; benzene; cyclohexane; metal hydride