Nitrogen and Carbon Isotopes Production
Development of Physical Bases of New Technologies of Nitrogen and Carbon Isotopes Production by Nonequilibrium Reactions Proceeding in a Post-Discharge Zone
Tech Area / Field
- FIR-ISO/Isotopes/Fission Reactors
3 Approved without Funding
Kurchatov Research Center, Russia, Moscow
- Institute of General Physics named after A.M. Prokhorov RAS / Natural Sciences Center, Russia, Moscow
- Tokyo Institute of Technology / Graduate School of Science and Engineering, Japan, Tokyo
Project summaryThe project concerns to a category - applied researches.
The purpose of the project is creation of physical bases for development of new technologies of 13С and 15N isotopes production. The development of new isotope production methods with the smaller cost price than known becomes rather urgent, because last years demand on 13С and 15N isotopes sharply grows for medicine application. The preparations marked by an 13С isotope are used for diagnostics of various stomach diseases. There is potential market of such diagnostic methods about 5 millions patients per one year. The downturn of cost of nitrogen and carbon isotopes can open a way to use in nuclear power nitrite fuel and to development of evolving technology of radioactive 14С isotope from graphite assembly worked in nuclear reactor.
First it was reported [E.M.Belenov, et al., JETP Lett. 18, 116 (1973)], that isotopic selectivity arising in nonequilibrium vibrational exchange between isotopic modifications of CO and N2 molecules may be used for isotope separation. Due to such exchange the upper vibrational levels of molecules became enriched by heavier isotopes and as a result the products of chemical reactions going with participation of the upper vibrational levels became enriched with 13С, 18О and 15N isotopes accordingly. The simplest way to excite vibrations of N2, CO and СО2 molecules is using of electrical discharge, however results of measurement of enrichment factor of reactions products are rather inconsistent when at of tests for the mass-spectrometer analysis are taken near a discharge zone.
In our recent article [N.M Gorshunov, S.V.Gudenko, JETP Letters, Vol.77, No.4, 2003, pp 162-166 ] it was reported, that more than 30-fold enrichment of atomic component of nitrogen with 15N isotope arises in a post-discharge zone, when the nitrogen flow passed through the pulsed-periodic discharge and atoms, which are formed in discharge, recombinate at tube walls. These results will be co-ordinated to results of work [V.Kudrle, A.Talsky, J.Janca, ICPIG, 1999, p84, Warshava], in which 10-fold enrichment of nitrogen atoms with the 15N was observed in a post-discharge zone of a microwave discharge.
It was reported [S.N.Andreev, et. al, J. of Technical Physics, vol.64, N5, p. 22-29, (1994)] that dissociation degree ratio of 12CO2 molecules and 13CO2 molecules was 2.5 when isotopic composition was measured by laser diode spectrometer (LDS) in a CO2 flow at the distance almost 10 meters from the discharge. It is possible that isotopic selective processes occurred in a post-discharge zone, because under similar conditions in the discharge, but at taking of tests for the mass- spectrometer analysis near a discharge zone there was no isotope enrichment within the limits of experiment accuracy. Registered in a post-discharge zone high meanings enrichment with 15N isotope of the nitrogen atomics and enrichment with 13С isotope of СО2 molecules together with simplicity of the used equipment specify an opportunity of creation on the basis of the investigated effects of new competitive methods of isotope separation of nitrogen and carbon. Systematic investigations of separation processes of nitrogen and carbon isotopes in a post-discharge zone and optimization are necessary for this purpose.
During execution of the project the dependencies of isotope enrichment parameter and concentration for nitrogen atoms and СО2 molecules should be received as function from discharge energy, speed of flow, isotope composition of initial molecules, pressure and temperature in a post-discharge zone. Concentrations of 14N and 15N atoms and 12СО2 and 13CO2 molecules will be measured by EPR and LD spectrometers in a post-discharge zone The most effective way of chemical linkage of nitrogen atoms and separation of isotope enrichment product NO2 from molecules of nitrogen should be chosen. From experimental results will be account the separated cascade of discharge cells capable to produce a isotopical product with a given enrichment degree.
The calculations of similar cascades for isotope separation of carbon and oxygen were made by the participants of the project in [N.M.Gorshunov, et. al, Khim. Vis. Energ. V.11, N2]. It was shown, that when achieve ratio of dissociation degrees of 12СО2 and 13CO2 molecules equal to 2.5 such cascade can produce 13С isotope at smaller expenses of the electric power and at the smaller sizes of the separation cascade, than at known separation plants. From calculations of the separate cascades it is possible to receive the data on the sizes of the cascade and about expenses of the electric power, for manufacture of a product with the given concentration of 13С and 15N isotopes. Development of the patent proposals on creation of the new technology of this isotope manufacture is planed during execution of the project.
The laboratory model of LDS will be created during the works, because it is required for large number of measurements of isotope composition of СО2 molecules in a post-discharge zone. Such LDS can form the basis for creation of cheaper and more convenient diagnostic tool than mass-spectrometer for the medical analysis of isotopic composition of СО2 molecules in breath test.
The leader of the project has 10 published articles on isotope separation at nonequilibrium reactions caused by intermolecular vibrational exchange. Recent publications, made in RRC “Kurchatov Institute” together with other participants of the project, have formed the basis for preparation of this project proposal.
The reliability of measurement results of isotope concentrations of reactions products during execution of the project is confirmed by qualification of the participants of the project. A.P.Babichev have 20 publications on isotope mass-spectrometer analysis, State Prize laureate A.I.Nadezhdinsky have 12 publications on the isotope and gas analysis with use of LDS and S.V.Gudenko have 10 publications on EPS analysis. The most part of the participants of the project have experience of work with ISTC (ISTC project #0830, project manager A.I Karchevsky, “Industrial plasma installation for production of isotopes gadolinium-157”).