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Application of surface-modified MH material for H 2 separation using temperature/pressure swing absorption–desorption was studied. The substrate alloy had the following composition LaNi 3.55 Co 0.75 Al 0.4 Mn 0.3 , and the surface modification was carried out through fluorination followed by aminosilane functionalization and electroless deposition of Pd. The material was found to have good poisoning tolerance towards surface adsorbates, even for the large (∼1.5 kg) batches. Feasibility of its application for H 2 separation from gas mixtures (up to 30% CO 2 and 100 ppm CO) was demonstrated by testing of a prototype H 2 separation system (∼280 g of MH in two reactors), and H 2 separation reactor (0.75 kg of MH). The H 2 separation was characterized by stable performances in the duration of 250 absorption/desorption cycles. However, the total process productivity was found to be limited by the sluggish H 2 absorption (partial H 2 pressure ⩽2.5 bar, temperature below 100 °C). In the presence of CO 2 and CO, additional deceleration of H 2 absorption was observed at space velocities of the feed gas below 5000 h −1 .

Earlier authors were offered a new method of increase of rate and selectivity of plasma chemical reactions with participation of hydrogen isotopes. This effect based on sorption activation of hydrogen by metal hydrides. Is shown that the sorption activation result in thermo emission of atomic hydrogen, ionized hydrogen atoms and molecules and excited hydrogen molecules from metal hydride surface. Ways of control various plasma chemical reactions by use of the sorption activation effect are discussed.

In this paper the theory of hydrogen vibrational excited molecule emission stimulated by plasma ion bombardment of metal hydride cathode surface in condition of gas discharge is discussed. The conception of direct momentum transfer due to collisions of both high-energy plasma ions and atoms with hydrogen atoms, dissolved in metal matrix, is assumed the theory as a basis. It is shown, that the efficiency of this process can be enough high to provide the hydrogen vibrational excited molecule emission out of metal hydride. It is shown, that the intensity of desorbed hydrogen flow linearly depends on flux of bombarding particles. The calculations, based on this mechanism, qualitatively agree with experimental data.