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A three-stage metal hydride hydrogen compressor (MHHC) system based in AB2-type alloys has been set-up. Every stage can be considered as a Sieverts-type apparatus. The MHHC system can work in the pressure and temperature ranges comprised from vacuum to 250 bar and from RT to 200 °C, respectively. An efficient thermal management system was set up for the operational ranges of temperature desired. It drops temperature shifts due to hydrogen expansion during stage coupling and hydrogen absorption/desorption in the alloys. Each reactor consists of a single and thin stainless-steel tube to maximize heat transfer. These were filled with similar amount of AB2 alloy. The MHHC system was able to produce a compression ratio as high as 84.7 for inlet and outlet hydrogen pressures of 1.44 and 122 bar for a temperature span of 23 °C – 120 °C.

A simulation analysis was performed to study the thermodynamic behavior of a realistic single stage hydride compressor, taking into account real H2 gas behavior by implementing several H2 equations of state, as well as realistic features in the hydrogen sorption properties of the hydride, like sloping plateau and hysteresis. The model was validated with experimental data from two different AB2 hydride systems, a low pressure Ti0.9Zr0.1Mn1.34V0.3 and a high pressure Ti0.9Zr0.1Mn1.47Cr0.4V0.2 alloys. The materials were characterized by X-ray powder diffraction (XRPD), Scanning Electron Microscopy (SEM) and Energy Dispersion X-ray spectroscopy (EDX). The numerical study was divided in three main parts: the effect of implementing real/ideal hydrogen gas models, a study of how the equations of state affect the Pressure composition Isotherm (P-c-T) determination and the influence of each model and realistic features of the P-c-T on the compressor simulation. Among all the models tested, Hemmes and Joubert real models give the more confident values for the compression ratio and final moles in the system volume at a final temperature of 353 K and pressures