SIMULTANEOUS SEPARATION OF ¹⁵N AND ¹⁴N BY ISOTOPIC EXCHANGE IN NITROX SYSTEM AT PRESSURE

Damian Axente^*, Ancuţa Balla, Cristina Marcu, Ştefan Gergely

National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Str. 400293 Cluj-Napoca, Romania

ABSTRACT

A new experimental study on simultaneous separation of ¹⁵N and ¹⁴N by ¹⁵N/¹⁴N exchange in Nitrox system under pressure is presented. The influence of the 10M HNO₃ flow rate and of the pressure on the isotopic separation was measured on a packed column equipped with product and waste refluxer. The experimental data show that the separation of ¹⁵N and ¹⁴N is improved by column operation at pressure. By using the additional column section in the top of waste refluxer all nitrogen oxides were converted into nitric acid and NO_x losses, in the top of isotopic separation plant, were not more observed. The pressure in the 0.6- 1.6 atm range of the sulfur dioxide, feeding the product refluxer, can be utilized providing similar results for ¹⁵N, ¹⁴N separation for 3.14 10M HNO₃ mL/cm²·min flow rate in the packed separation column.

Keywords: ¹⁵N, ¹⁴N separation, isotopic exchange, Nitrox system, pressure, packed separation column.