| abstract |
Obtain high purity isotope gas at low cost. For example, when 13 CH 4 is separated from methane gas to obtain high-purity 13 CH 4, up to a certain concentration, using the difference in adsorptivity between 12 CH 4 and 13 CH 4 to the adsorbing material, 13 CH 4 is concentrated, and thereafter 13 CH 4 is concentrated by a separation method using distillation utilizing the difference in boiling points. |