To extract hydrogen from ammonia, which is a hydrogen carrier, it is necessary to separate hydrogen and nitrogen and then extract pure hydrogen gas so that the separation membrane has to be developed. Since Ti has excellent hydrogen solubility, Ti/Polyimide (PI) laminated membrane would be developed to further improve the hydrogen permeability and separation factor for hydrogen and nitrogen gases. The hydrogen/nitrogen permeability characteristics were evaluated using a gas permeability measurement system as the same as in our previous study and calculated the separation factor. The results showed that the Ti/PI laminate membrane exhibited a higher hydrogen permeability and that is a positive effect of Ti laminated but less separation characteristics than only PI membrane. On the other hand, the Ni/PI membrane, experimented in our previous study, exhibited a lower hydrogen permeability and higher separation properties than the PI membrane. From the results, it was found that the temperature dependence of the laminated membranes depends on the solubility of the laminated metal on the surface of PI membrane rather than the permeability.
Suzuki et al. (Wed,) studied this question.