Production Technology Status and Development Trend of Stable Isotopes C, N and O

It has been over half a century since the successful separation of table isotopes carbon, nitrogen and oxygen. The production capacity achieved three levels improvements from the laboratory-scale of one hundred grams, to the pilot production of several kilograms, and mass production of one hundred kilograms. The separation technologies also achieved three generation progress. The first generation of separation technology was represented by thermal diffusion method, chromatography, and ion exchange; the second generation of separation technology was represented by chemical exchange, distillation; the third generation of separation technology was characterized by the techniques innovation of material recycling, energy coupling, energy saving, and large-scale production capacity. At present, ¹³C is wholly produced by cryogenic distillation method, ¹⁵N is produced by NO/HNO₃ chemical exchange and NO cryogenic distillation method, and ¹⁸O is manufactured by distillation of water, and cryogenic distillation of NO and O₂. The same features of these separation methods are achieving energy coupling, materials recycling, large-scale producing, and energy conservation in the process. In the future, it will be the theme of stable isotope industry to develop environment-friendly, raw materials available, energy saving, low-cost, and large-scale manufacturing technology through continuous technological innovation.