MODELING ACTIVATION PROCESSES IN A POROUS FLOW-THROUGH MH-ACTIVATOR

On the basis of experimental data it has been shown that the effect of hydrogen MH-activation leads to the redistribution of the contributio n of the separate elementary stages to the energy balance and the comp onent composition of the ionization products in Neer's ion source. Thi s results in an increase of the ionization efficiency and of the gas a nd energy efficiency of the source in the sense of forming atomic H+ i ons. The heterogeneous processes in the systems (hydride-forming inter metallic compound-hydrogen (deuterium)) have been investigated, and th e increase in the energy state of hydrogen and its isotopes has been e stablished. The kinds of excited slates are the following: atomic hydr ogen, the electron-excited state of hydrogen atoms and molecules, and vibrational states of H-2 (v not equal 0) molecule. Mathematical mode lling of the flow in a porous flow-through MH-activator was carried ou t using the assumption that the hydrogen flow through a unit area of t he cross-section is determined by three types of diffusion: gas diffus ion of H-2 within the porous volume, transfer of chemisorbed atoms ove r the pore surface, and solid-phase diffusion of hydrogen atoms dissol ved in the MH-activator crystal lattice. It was shown that the most pr obable type of excitation of H-2 is the vibrational excitation of H-2 (v = 1) and the full degree of excitation of hydrogen having passed t hrough a layer of MH-activator, beta = 20%, and the fraction of desorb ed molecules which have an excessive energy in the form of vibrational excitation (v > 1) makes up alpha(a) approximate to 35-40%. Copyright (C) 1996 International Association for Hydrogen Energy