CA1127978A - Isotopic separation process with improved efficiency - Google Patents
Isotopic separation process with improved efficiencyInfo
- Publication number
- CA1127978A CA1127978A CA331,175A CA331175A CA1127978A CA 1127978 A CA1127978 A CA 1127978A CA 331175 A CA331175 A CA 331175A CA 1127978 A CA1127978 A CA 1127978A
- Authority
- CA
- Canada
- Prior art keywords
- chromatogram
- platform
- tail
- head
- boron
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D59/00—Separation of different isotopes of the same chemical element
- B01D59/28—Separation by chemical exchange
- B01D59/30—Separation by chemical exchange by ion exchange
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Treatment Of Liquids With Adsorbents In General (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A method for the separation of isotopes is di-sclosed, by which, in a chromatographic column an i-sotopic platform is maintained by forming a very wide absorption band in order to separate sharply the en-riched zones with the depleted ones at the head and the tail of the chromatogram: no product is removed from the column until the atomic fraction of the iso-tope sought for has reached the required enrichment value.
A method for the separation of isotopes is di-sclosed, by which, in a chromatographic column an i-sotopic platform is maintained by forming a very wide absorption band in order to separate sharply the en-riched zones with the depleted ones at the head and the tail of the chromatogram: no product is removed from the column until the atomic fraction of the iso-tope sought for has reached the required enrichment value.
Description
llZ7978 This invention relates to a method of chromato-graphic isotope separation which maintain a platform (in isotopic equilibrium with the originally fed solution) in the interior of the chromatogram, thus makinq possible a more efficient production of the enriched isotope which is desired.
Generally, the present invention provides in a process for isotope separation by liquid or gaseous chromato-graphy in which a platform is maintained in isotopic equilib-rium with the originally introduced influent in the interior of the chromatograph, the improvement consisting in that the isotopic platform is maintained by forming in a chromatographic column a very wide absorption band in which enriched and depleted zones which are formed at the head and the tail of the chromatograph always remain separated from one another.
In accordance with the present invention there may be supplied to a central portion of the chromatograph an additional amount of influent without discontinuing the process.
With the method of the present invention, it becomes possible to separate lithium-6 from lithium-7, boron-10 from boron-ll, and also other isotopes, such as uranium-235 from uranium 238.
This invention relates to a method which makes all the operations simpler and improves the efficiency of the total separation in liquid or gaseous chromatography processes to produce enriched isotopes.
In particular, chromatographic processes of this invention for producinq enriched isotopes may involve the following tWG stages:
(1) a preliminary enrichment stage (start up)
Generally, the present invention provides in a process for isotope separation by liquid or gaseous chromato-graphy in which a platform is maintained in isotopic equilib-rium with the originally introduced influent in the interior of the chromatograph, the improvement consisting in that the isotopic platform is maintained by forming in a chromatographic column a very wide absorption band in which enriched and depleted zones which are formed at the head and the tail of the chromatograph always remain separated from one another.
In accordance with the present invention there may be supplied to a central portion of the chromatograph an additional amount of influent without discontinuing the process.
With the method of the present invention, it becomes possible to separate lithium-6 from lithium-7, boron-10 from boron-ll, and also other isotopes, such as uranium-235 from uranium 238.
This invention relates to a method which makes all the operations simpler and improves the efficiency of the total separation in liquid or gaseous chromatography processes to produce enriched isotopes.
In particular, chromatographic processes of this invention for producinq enriched isotopes may involve the following tWG stages:
(1) a preliminary enrichment stage (start up)
(2) a production stage.
~`
`` llZ7978 The preliminary enrichment stage is that in which the chromatographic apparatus is started and run without drawing any product stream until the atomic fraction of the expected isotope has attained the requested value at the head or the tail portion of the chromatogram.
The subsequent production stage is that in which a product of the desired atomic fraction is drawn in a semi-continuous way, or a continuous way, from the head, or the tail of the chromatogram.
The efficiency of the separation of the chromato-graphic isotopic separation of the prior art shows a tendency to worsen, in fact, because the enriched and the depleted areas overlap and cause an isotope intermingling.
In the present method, the chromatography is carried out in such a way that the fronts of displacements are formed at the head and/or at the tail of the chromatogram and the sum of the concentrations of the two isotopic species remains constant.
The chromatographic band is made wide enough so that the enriched and the depleted areas remain always separated from one another, no mutual overlapping being experienced therebetween.
The prominent features of the method according to the present invention can be summarized as follows:
(1) prevention of the isotope intermingling while maintaining a platform (in isotopic equilibrium with the fed in solution) between the enriched and the depleted area.
(2) prevention of the widening of the enriched and the depleted areas as caused by changes in the total con-centration.
~`
`` llZ7978 The preliminary enrichment stage is that in which the chromatographic apparatus is started and run without drawing any product stream until the atomic fraction of the expected isotope has attained the requested value at the head or the tail portion of the chromatogram.
The subsequent production stage is that in which a product of the desired atomic fraction is drawn in a semi-continuous way, or a continuous way, from the head, or the tail of the chromatogram.
The efficiency of the separation of the chromato-graphic isotopic separation of the prior art shows a tendency to worsen, in fact, because the enriched and the depleted areas overlap and cause an isotope intermingling.
In the present method, the chromatography is carried out in such a way that the fronts of displacements are formed at the head and/or at the tail of the chromatogram and the sum of the concentrations of the two isotopic species remains constant.
The chromatographic band is made wide enough so that the enriched and the depleted areas remain always separated from one another, no mutual overlapping being experienced therebetween.
The prominent features of the method according to the present invention can be summarized as follows:
(1) prevention of the isotope intermingling while maintaining a platform (in isotopic equilibrium with the fed in solution) between the enriched and the depleted area.
(2) prevention of the widening of the enriched and the depleted areas as caused by changes in the total con-centration.
(3) the central portion of the chromatogram can besupplied with additional amounts of feeding solution without discontinuing the process.
The result is a more efficient production of the expected enriched isotope.
In drawings which illustrate embodiments of the invention:
Figure 1 shows, in a diagrammatical fashion a set of resin-containing columns for carrying out the process of this invention;
Figure 2 shows the chromatogram of lithium, with the maintenance of the isotopic platform, the Li-acetate con-centrations being plotted on the ordinate axis in mol/litre as-a function of the position of the chromatogram, expressed in metres, as measured from the head of the band and plotted on the abscissa axis;
Figure 3 is a chromatogram like that of Figure 2, but without maintaining the isotopic platform;
Figure 4 shown a single column for the enrichment of boron-10;
Figure S represents the chromatogram of boron with the maintenance of the isotopic platform;
Figure 6 shows a chromatogram similar to that of Figure 5, but without maintaining the isotopic platform;
Figure 7 diagrammatically shows the arrangement of the set of columns for the production of boric acid enriched with boron 10, and Figure 8 represents the chromatogram of boron with the maintenance of the isotopic platform.
I More particularly, figure 1 diagrammatically shows ; the arrangement of columns set for the production of lithium-6.
The reference numeral 1 indicates the solution of lithium acetate employed for the formation of the lithium absorpton band. The numeral 2 indicates the solution of eluent sodium acetate, whereas 3 indicates the solution of acetic acid used for regenerating the resin. The hatched portion 4 - 2a -11æ7~8 of the columns indicates the lithium-absorption band. The speckled portion indicates the resin which has been eluted in the sodium-form R-Na, 5, or in the acidic form, R-H, at 6.
Figure 2 shows the chromatogram of lithium with the maintenance of the isotopic platform having a length of 6 metres and obtained as a result of the migration of the absoption band over a length of 202 metres.
The elution curve, 1, indicates the concentration of lithium expressed in miles per litre and plotted on the ordinates axis on the left as a ~unction of the position on the chromatogram expressed in metres and reported on the abscissae axis.
The plot of the atomic fraction (ratio of the number of atoms of an isotope present in the element, to the number of atoms in total), 2, indicates the percentage value of the atomic fraction of lithium-6 as reported on the ordinates axis on the left as a function of the position on the chromatogram in metres, which is plotted on the abscissae axis.
The dotted line, 3, indicates the original atomic fraction of lithium-6 which is 7.2%.
Figure 3 shows a chromatoyram like that of Figure 2 but without maintaining the isotopic platform: the symbols are the same as for Figure 2.
Figure 4 shows a single column for the enrichment of boron-10.
The reference numeral 1 indicates the solution of boric acid used for the absorption, while 2 is the eluent water.
The hatched portion 3 of the column indicates the boron-absorption band.
The speckled portion, 4, indicates the already eluted resin.
- 2b -~797~
Figure 5 shows the chromatogram of boron with the maintenance of the isotopic platform in correspondence with the original atomic fraction of boron-10, which is 19.8%.
The elution curve, 1, indicates the concentration of boric acid expressed in miles per litre and reported on the axis of the ordinates, on the left, as a function of the position on the chromatogram, which is expressed in metres and is reported on the abscissae axis.
Figure 6 shows a chromatogram similar to that of Figure 5 but without maintaining the isotopic platform, the symbols being the same as in Figure 5.
! Figure 7 diagrammatically shows the arrangement of the set of columns for the production of the boric acid enriched with boron-10, the symbols being the same as in Figure 4.
Figure 8 shows the chromatogram of boron with the maintenance of the isotopic platform in the case of the production of the 90%-boron-10, the symbols being the same as in Figure 5.
By way of example only and without any limitation, there will be described in more detail a few examples of practice of the method in question by liquid-phase chromato-graphy.
Naturally occurring lithium is composed by two . isotopes, viz.: lithium-6 (7.2%) and lithium-7 (92.8%).
, I
- 2c -~8 A set of columns such as shown in Figure 1 (each column has a diameter of 22 mm and a length of B 1300 mm) were filled with an ion exchange resin Dowex 50 W up to a height of 1200 mm andsaid resin was con-verted to the acidic form R-H. An absorption band was formed by feeding the column set with a 0.3 M aqueous solution of lithium acetate~ CH3COOLi~ and then a chro-matography run was carried out by eluting the absorp-tion band with a 0.3 M aqueous solution of sodium a-cetate, CH3COONa.
By so doing~ it has been possible to enrich the head with lithium-7 and the tail of the absorption band with lithium-6.
I) BY maintainin~ an isotopic platform:
A lithium-absorption band 6-metre wide was form-ed and shifted through the column6. After migration o-~er an overall distance of 202 metres, the atomic frac-tion of lithium-6 at the tail end of the band was in-creased from 7~2% to 1~0%~
It has thus been possible to produce 15~O-en-riched lithium-6 at the velocity Of 2~9 millimols per square cm and per day by supplying naturally occurring lithium to the central shank of` the chromatogramO On the band head, the atomic fraction of lithium-6 was re-duced from 7~2% to 2~9% only~ upon migration over a di-stance of 202 metres~ as shown by Figure 2 of the ac-companying drawings.
~I) ~
A 3-metre wide lithium colu~m was formcd and shifted through the column set.
To enrich the atomic fraction of lithium-6 on the head of the band from 7~2% to 15.0C~o the band had to be shifted over an overall distance of 450 metres.
At this point, lithi~m-6 ~ehcA b~ ~ could 3~ have been produced at a velocity of 1.4 millimol pcr 6quare cm daily.
~lZ79~
_ 4 -It became difficult, however~ to supply fresh feeding solution to the band center without breaking the chromatogram, so that the production ~elocity de-cayed~ as shown in Figure 3.
Naturally occuring boron consists of two iso-topes~ viz.: boron-10 ( 19~8%) and boron-11 (80.2~).
A column such as shown on ~igure 4 of the ac-companying drawings and having a diameter of 22 mm and a height of 4100 mm was filled with an anionic exchange resin~ weakly basic, Diaion WA 21 in the form of a free base to a height of 4000 mm~ said resin being converted to the basic form R-OH and washed with pure water.
The column was then charged with an aqueous so-lution of boric acid to form an absorption band and a chromatography was carried out by eluting the boron band with water.
By so doing~ it has been possible to enrich the head with boron-11 and the band tail with boron-100 I) Bv maintainin~ an isotopic Platform A 4-metre ionic exchange column was first ba-lanced with 5.0 litres of a 0.1 M aqueous solution of boric acid.
The front portion of the absorption band was dumped so that the enriched boron-11 was not recoveredO
A chromatography was effected by eluting the absorption band with water and boron-10 was enriched f`rom 19~8% to 33.35~ at the tail ~nd of the band. The width of the enriched zone was 34 centimetres as shown in Figure 5 of the accompany~ng drawings.
II) 1~ithout maintainin~ an isotopic platf~rm Upon originally charging the column with 2.0 litres of a 0.1 M solution of boric acid, it proved impossible to carry out any shift chromatography, or to maintain an isotopic platform in the intorior of the 11*7978' chromatogram.
Upon migration over a distance of 4 metres, the atomic fraction of boron-10 at the tail end of the band attained only 25.8~ and the width of the enriched zone was 96 centimetres as shown in Figure 6 of the accom-panying drawings.
EXAMPLE 3 - P~ODUCTION 0~ 90',~-BORON-10 The production of boron-10 at a 90% rating was carried out with the same procedure as described in the previous example 2 hereof.
A set of columns such as shown in Figure 7 of the accompanying drawings~ each column having a diame-ter of 21 mm and a length of 1100 mm~ were filled with resin up to a height ~f 1000 mm and the resin was pre-liminarily processed as described in example 2 hereof.
Each column was balanced~ at the outset~ with 2.0 litres of 0.1 M boric acid solution.
Each ~olumn was fed by an excess of the 901u-tion so that the zones which had been depleted of bo-ron-10 were dumped~ leaving the resin both in chemical and isotopic equilibrium with the fed in solution~
The columns were then serially connected by vinyl chloride pipes having an inside diameter of 0.8 mm and a chromatography was carried out by feeding wa-ter to the first column of the set and shifting the bo-ric acid through the remaining columns. The width of the absorption band was kept very wide so that a plat-form (in isotopic equilibrium with the incoming solu-tion) was maintained during the entire operation.
After that the boric acid had completely been eluted from the first column, the column was withdrawn from the column set, balanced once again with the feed-ing solution and connected, in the streamline direc-tion~ at thc end of the set.
By so doingS the absorption band was easily shifted along a long distance without discontinuing ~2~
the procedure. After that the band had migrated over an overall distance of 250 metres, the atomic fraction of boron-10 at the tail end of the band was enriched to 90% and 90%-enriched boron-10 was produced at a velocity of 0.09 millimol per square cm daily, as shown in Figure 8.
As these example clearly show, enriched isotopes can be produced more efficiently if an isotopic platform is maintained in the interior of the separation chromatogram.
It can be appreciated that a length of chromatogram of 250 metres corresponds, at the band tail, to the band of 90%-enriched boron-10.
While the invention has been described in connection with a few defininte embodiments thereof, the basic idea of the invention can be embodied otherwise within the purview of those skilled in the art.
Moreover, without departing from the scope of the invention, modifications and changes can be introduced in the reduction to actual practice within the scope of the invention as set forth hereinbefore.
The result is a more efficient production of the expected enriched isotope.
In drawings which illustrate embodiments of the invention:
Figure 1 shows, in a diagrammatical fashion a set of resin-containing columns for carrying out the process of this invention;
Figure 2 shows the chromatogram of lithium, with the maintenance of the isotopic platform, the Li-acetate con-centrations being plotted on the ordinate axis in mol/litre as-a function of the position of the chromatogram, expressed in metres, as measured from the head of the band and plotted on the abscissa axis;
Figure 3 is a chromatogram like that of Figure 2, but without maintaining the isotopic platform;
Figure 4 shown a single column for the enrichment of boron-10;
Figure S represents the chromatogram of boron with the maintenance of the isotopic platform;
Figure 6 shows a chromatogram similar to that of Figure 5, but without maintaining the isotopic platform;
Figure 7 diagrammatically shows the arrangement of the set of columns for the production of boric acid enriched with boron 10, and Figure 8 represents the chromatogram of boron with the maintenance of the isotopic platform.
I More particularly, figure 1 diagrammatically shows ; the arrangement of columns set for the production of lithium-6.
The reference numeral 1 indicates the solution of lithium acetate employed for the formation of the lithium absorpton band. The numeral 2 indicates the solution of eluent sodium acetate, whereas 3 indicates the solution of acetic acid used for regenerating the resin. The hatched portion 4 - 2a -11æ7~8 of the columns indicates the lithium-absorption band. The speckled portion indicates the resin which has been eluted in the sodium-form R-Na, 5, or in the acidic form, R-H, at 6.
Figure 2 shows the chromatogram of lithium with the maintenance of the isotopic platform having a length of 6 metres and obtained as a result of the migration of the absoption band over a length of 202 metres.
The elution curve, 1, indicates the concentration of lithium expressed in miles per litre and plotted on the ordinates axis on the left as a ~unction of the position on the chromatogram expressed in metres and reported on the abscissae axis.
The plot of the atomic fraction (ratio of the number of atoms of an isotope present in the element, to the number of atoms in total), 2, indicates the percentage value of the atomic fraction of lithium-6 as reported on the ordinates axis on the left as a function of the position on the chromatogram in metres, which is plotted on the abscissae axis.
The dotted line, 3, indicates the original atomic fraction of lithium-6 which is 7.2%.
Figure 3 shows a chromatoyram like that of Figure 2 but without maintaining the isotopic platform: the symbols are the same as for Figure 2.
Figure 4 shows a single column for the enrichment of boron-10.
The reference numeral 1 indicates the solution of boric acid used for the absorption, while 2 is the eluent water.
The hatched portion 3 of the column indicates the boron-absorption band.
The speckled portion, 4, indicates the already eluted resin.
- 2b -~797~
Figure 5 shows the chromatogram of boron with the maintenance of the isotopic platform in correspondence with the original atomic fraction of boron-10, which is 19.8%.
The elution curve, 1, indicates the concentration of boric acid expressed in miles per litre and reported on the axis of the ordinates, on the left, as a function of the position on the chromatogram, which is expressed in metres and is reported on the abscissae axis.
Figure 6 shows a chromatogram similar to that of Figure 5 but without maintaining the isotopic platform, the symbols being the same as in Figure 5.
! Figure 7 diagrammatically shows the arrangement of the set of columns for the production of the boric acid enriched with boron-10, the symbols being the same as in Figure 4.
Figure 8 shows the chromatogram of boron with the maintenance of the isotopic platform in the case of the production of the 90%-boron-10, the symbols being the same as in Figure 5.
By way of example only and without any limitation, there will be described in more detail a few examples of practice of the method in question by liquid-phase chromato-graphy.
Naturally occurring lithium is composed by two . isotopes, viz.: lithium-6 (7.2%) and lithium-7 (92.8%).
, I
- 2c -~8 A set of columns such as shown in Figure 1 (each column has a diameter of 22 mm and a length of B 1300 mm) were filled with an ion exchange resin Dowex 50 W up to a height of 1200 mm andsaid resin was con-verted to the acidic form R-H. An absorption band was formed by feeding the column set with a 0.3 M aqueous solution of lithium acetate~ CH3COOLi~ and then a chro-matography run was carried out by eluting the absorp-tion band with a 0.3 M aqueous solution of sodium a-cetate, CH3COONa.
By so doing~ it has been possible to enrich the head with lithium-7 and the tail of the absorption band with lithium-6.
I) BY maintainin~ an isotopic platform:
A lithium-absorption band 6-metre wide was form-ed and shifted through the column6. After migration o-~er an overall distance of 202 metres, the atomic frac-tion of lithium-6 at the tail end of the band was in-creased from 7~2% to 1~0%~
It has thus been possible to produce 15~O-en-riched lithium-6 at the velocity Of 2~9 millimols per square cm and per day by supplying naturally occurring lithium to the central shank of` the chromatogramO On the band head, the atomic fraction of lithium-6 was re-duced from 7~2% to 2~9% only~ upon migration over a di-stance of 202 metres~ as shown by Figure 2 of the ac-companying drawings.
~I) ~
A 3-metre wide lithium colu~m was formcd and shifted through the column set.
To enrich the atomic fraction of lithium-6 on the head of the band from 7~2% to 15.0C~o the band had to be shifted over an overall distance of 450 metres.
At this point, lithi~m-6 ~ehcA b~ ~ could 3~ have been produced at a velocity of 1.4 millimol pcr 6quare cm daily.
~lZ79~
_ 4 -It became difficult, however~ to supply fresh feeding solution to the band center without breaking the chromatogram, so that the production ~elocity de-cayed~ as shown in Figure 3.
Naturally occuring boron consists of two iso-topes~ viz.: boron-10 ( 19~8%) and boron-11 (80.2~).
A column such as shown on ~igure 4 of the ac-companying drawings and having a diameter of 22 mm and a height of 4100 mm was filled with an anionic exchange resin~ weakly basic, Diaion WA 21 in the form of a free base to a height of 4000 mm~ said resin being converted to the basic form R-OH and washed with pure water.
The column was then charged with an aqueous so-lution of boric acid to form an absorption band and a chromatography was carried out by eluting the boron band with water.
By so doing~ it has been possible to enrich the head with boron-11 and the band tail with boron-100 I) Bv maintainin~ an isotopic Platform A 4-metre ionic exchange column was first ba-lanced with 5.0 litres of a 0.1 M aqueous solution of boric acid.
The front portion of the absorption band was dumped so that the enriched boron-11 was not recoveredO
A chromatography was effected by eluting the absorption band with water and boron-10 was enriched f`rom 19~8% to 33.35~ at the tail ~nd of the band. The width of the enriched zone was 34 centimetres as shown in Figure 5 of the accompany~ng drawings.
II) 1~ithout maintainin~ an isotopic platf~rm Upon originally charging the column with 2.0 litres of a 0.1 M solution of boric acid, it proved impossible to carry out any shift chromatography, or to maintain an isotopic platform in the intorior of the 11*7978' chromatogram.
Upon migration over a distance of 4 metres, the atomic fraction of boron-10 at the tail end of the band attained only 25.8~ and the width of the enriched zone was 96 centimetres as shown in Figure 6 of the accom-panying drawings.
EXAMPLE 3 - P~ODUCTION 0~ 90',~-BORON-10 The production of boron-10 at a 90% rating was carried out with the same procedure as described in the previous example 2 hereof.
A set of columns such as shown in Figure 7 of the accompanying drawings~ each column having a diame-ter of 21 mm and a length of 1100 mm~ were filled with resin up to a height ~f 1000 mm and the resin was pre-liminarily processed as described in example 2 hereof.
Each column was balanced~ at the outset~ with 2.0 litres of 0.1 M boric acid solution.
Each ~olumn was fed by an excess of the 901u-tion so that the zones which had been depleted of bo-ron-10 were dumped~ leaving the resin both in chemical and isotopic equilibrium with the fed in solution~
The columns were then serially connected by vinyl chloride pipes having an inside diameter of 0.8 mm and a chromatography was carried out by feeding wa-ter to the first column of the set and shifting the bo-ric acid through the remaining columns. The width of the absorption band was kept very wide so that a plat-form (in isotopic equilibrium with the incoming solu-tion) was maintained during the entire operation.
After that the boric acid had completely been eluted from the first column, the column was withdrawn from the column set, balanced once again with the feed-ing solution and connected, in the streamline direc-tion~ at thc end of the set.
By so doingS the absorption band was easily shifted along a long distance without discontinuing ~2~
the procedure. After that the band had migrated over an overall distance of 250 metres, the atomic fraction of boron-10 at the tail end of the band was enriched to 90% and 90%-enriched boron-10 was produced at a velocity of 0.09 millimol per square cm daily, as shown in Figure 8.
As these example clearly show, enriched isotopes can be produced more efficiently if an isotopic platform is maintained in the interior of the separation chromatogram.
It can be appreciated that a length of chromatogram of 250 metres corresponds, at the band tail, to the band of 90%-enriched boron-10.
While the invention has been described in connection with a few defininte embodiments thereof, the basic idea of the invention can be embodied otherwise within the purview of those skilled in the art.
Moreover, without departing from the scope of the invention, modifications and changes can be introduced in the reduction to actual practice within the scope of the invention as set forth hereinbefore.
Claims (6)
1. In a process for isotope separation by liquid or gaseous chromatography in which a platform is maintained in isotopic equilibrium with the originally introduced influent in the interior of the chromatograph, the improvement consisting in that the isotopic platform is maintained by forming in a chromatographic column a very wide absorption band in which enriched and depleted zones which are formed at the head and the tail of the chromatograph always remain separated from one another.
2. A process according to claim 1, characterized in that there is supplied to a central zone of the chroma-tograph an additional amount of influent without discontinuing the process.
3. A process according to claim 1, having a preliminary startup stage and a production stage characterized in that the preliminary startup stage, which is carried out by maintaining a platform without withdrawing any product until the atomic fraction of the expected isotope has reached the required enrichment value at the head or the tail of the chromatogram, is followed by a production stage in which the product of the desired atomic fraction is withdrawn semi-continuously or continuously from the head or the tail of the chromatogram.
4. A process according to claim 2, having a preliminary startup stage and a production stage characterized in that the preliminary startup stage, which is carried out by maintaining a platform without withdrawing any product until the atomic fraction of the expected isotope has reached the required enrichment value at the head or the tail of the chromatogram, is followed by a production stage in which the product of the desired atomic fraction is withdrawn semi-continuously or continuously from the head or the tail of the chromatogram.
5. A process according to any one of claims 1, 2 and 3, characterized in that the isotope obtained is lithium-6, boron-10 or uranium-235.
6. A process according to claim 4, characterized in that the isotope obtained is lithium-6, boron-10 or uranium-235.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT25353A/78 | 1978-07-05 | ||
| IT25353/78A IT1097473B (en) | 1978-07-05 | 1978-07-05 | METHOD TO INCREASE PRODUCTION EFFICIENCY IN ISOTOPIC SEPARATION PROCESSES |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1127978A true CA1127978A (en) | 1982-07-20 |
Family
ID=11216444
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA331,175A Expired CA1127978A (en) | 1978-07-05 | 1979-07-04 | Isotopic separation process with improved efficiency |
Country Status (9)
| Country | Link |
|---|---|
| JP (1) | JPS5547124A (en) |
| BE (1) | BE877508A (en) |
| CA (1) | CA1127978A (en) |
| CH (1) | CH643751A5 (en) |
| DE (1) | DE2927212C2 (en) |
| FR (1) | FR2433968A1 (en) |
| GB (1) | GB2024648B (en) |
| IT (1) | IT1097473B (en) |
| NL (1) | NL183337C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4732581A (en) * | 1986-05-08 | 1988-03-22 | Cheh Christopher H | Gas chromatographic method for separating hydrogen isotopes |
| DE19817529B4 (en) * | 1998-04-09 | 2005-04-21 | Institut für Umwelttechnologien GmbH | Method and device for enriching the carbon isotopes by means of a gas chromatographic pulse method |
| US10018543B1 (en) * | 2013-06-05 | 2018-07-10 | Elemental Scientific, Inc. | Purifying an element from a sample matrix for isotopic analysis |
| CN103949159B (en) * | 2014-05-15 | 2015-11-25 | 中国工程物理研究院核物理与化学研究所 | A kind of radio isotope 14the separation method of C |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2889205A (en) * | 1956-02-29 | 1959-06-02 | Iowa State College Res Found | Method of separating nitrogen isotopes by ion-exchange |
| GB1247736A (en) * | 1967-10-02 | 1971-09-29 | Nippon Rensui Kabushiki Kaisha | Lithium separation |
-
1978
- 1978-07-05 IT IT25353/78A patent/IT1097473B/en active
-
1979
- 1979-07-03 GB GB7923040A patent/GB2024648B/en not_active Expired
- 1979-07-04 FR FR7917394A patent/FR2433968A1/en active Granted
- 1979-07-04 CA CA331,175A patent/CA1127978A/en not_active Expired
- 1979-07-05 BE BE0/196147A patent/BE877508A/en not_active IP Right Cessation
- 1979-07-05 DE DE2927212A patent/DE2927212C2/en not_active Expired
- 1979-07-05 CH CH630079A patent/CH643751A5/en not_active IP Right Cessation
- 1979-07-05 NL NLAANVRAGE7905256,A patent/NL183337C/en not_active IP Right Cessation
- 1979-07-05 JP JP8450779A patent/JPS5547124A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| DE2927212C2 (en) | 1985-02-07 |
| IT7825353A0 (en) | 1978-07-05 |
| GB2024648B (en) | 1982-09-15 |
| CH643751A5 (en) | 1984-06-29 |
| NL183337B (en) | 1988-05-02 |
| NL7905256A (en) | 1980-01-08 |
| BE877508A (en) | 1980-01-07 |
| FR2433968A1 (en) | 1980-03-21 |
| IT1097473B (en) | 1985-08-31 |
| DE2927212A1 (en) | 1980-02-14 |
| GB2024648A (en) | 1980-01-16 |
| FR2433968B1 (en) | 1984-03-02 |
| NL183337C (en) | 1988-10-03 |
| JPS5547124A (en) | 1980-04-03 |
| JPS6260136B2 (en) | 1987-12-15 |
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