Process and device for separation with variable-length chromatographic zones

• US 6,712,973 B2
• Filed: 03/26/2002
• Issued: 03/30/2004
• Est. Priority Date: 10/29/1998
• Status: Expired due to Term

• Current Assignee: Institut Francais Du Petrole, Novasep Co.
• Original Assignee: Institut Francais Du Petrole, Novasep Co.
• Inventors: Nicoud, Roger Marc, Adam, Phillippe, Bailly, Michel, Ludemann-Hombourger, Olivier
• Primary Examiner(s): Therkorn, Ernest G.
• Application Number:
  US10/105,220
• Publication Number:
  US 20020174769A1
• Time in Patent Office: 735 Days
• Field of Search: 210/635, 210/656, 210/659, 210/662, 210/672, 210/198.2
• US Class Current: 210/659
• CPC Class Codes: B01D 15/1828 characterized by process features
• CPC Class Codes: B01D 2215/023 Simulated moving beds

Abstract

A process for separating at least one component of a mixture in a set of closed-loop chromatographic columns is described, whereby the loop comprises at least one feedstock injection point, a raffinate draw-off point, an eluant injection point, and an extract draw-off point, in which a determination is made between an injection point and a draw-off point or vice-versa a chromatographic zone, and at the end of a given period of time, all of the injection points and draw-off points are shifted by the same number of columns or column sections and advantageously by one column or column section in a given direction that is defined relative to that of the flow of a main fluid that circulates through the loop. During the period, the shifting of different injection points and draw-off points of at least one column or column section is done at different times in such a way that the lengths of the zones that are defined by said different points are variable. The process is useful for the separation particularly of stereoisomers for pharmaceuticals.

Claims

1. A non-simulated-moving-bed (non-SMB) process for separating at least one component of a mixture that contains it, comprising introducing said mixture into a non-SMB device that has a set of chromatographic columns or chromatographic column sections that contain an adsorbent and are arranged in series and in a loop, whereby the loop comprises at least one feedstock injection point, a raffinate draw-off point, an eluant injection point, and an extract draw-off point, in which a chromatographic zone is determined between an injection point and a draw-off point or vice-versa, and wherein at the end of a given period of time all of the injection and draw-off points are shifted by the same number of columns or column sections, and during said period, shifting different injection and draw-off points at different times such that the lengths of the zones that are defined by said different points are variable.

2. A non-SMB process according to claim 1, wherein the succession of the following stages is carried out at least once:

At moment t1 during said period, in a given direction, the position of the injection point or draw-off point is shifted relative to at least one zone by a column or column section, then at a moment t2 during said period, the position of the injection point or draw-off point that is relative to at least one other zone is shifted in the same direction by a column or column section, and the operation is repeated if necessary such that after said time period, the same column configuration or column section configuration as the initial configuration is regained with a shifting of all of the positions of the injection points and draw-off points of the same number of columns or column sections.

3. A non-SMB process according to claim 1, wherein the succession of the following stages is carried out at least once:

At moment t1 during said period, in a given direction, the position of the injection point or draw-off point is shifted relative to at least one zone by a column or column section, in such a way as to increase the length of said zone and to reduce the length of the zone that is adjacent to said zone, then at a moment t2 during said period, the position of an injection point or draw-off point that is relative to at least one other zone is shifted in the same direction by a column or column section, in such a way as to increase the length of said other zone and to reduce the length of the zone that is adjacent to said other zone, and the operation is repeated if necessary such that after said time period, the same column configuration or column section configuration as the initial configuration is regained with a shifting of all of the positions of the injection points and draw-off points of the same number of columns or column sections.

4. A non-SMB process according to claim 1, wherein at moment t1, the position of the extract draw-off point and the position of the raffinate draw-off point are shifted by a column or column section, then at a moment t2 during said period, the position of the feedstock injection point and the position of the eluant injection point are shifted by a column or column section.

5. A non-SMB process according to claim 1, wherein during the period, all of the shiftings of injection positions or draw-off positions are carried out with a time phase shift that is approximately constant and advantageously with a phase shift that is at least equal to one quarter-period.

6. A non-SMB process according to claim 1, wherein during the period, shiftings of the positions of the injection points or draw-off points are carried out with a non-constant time phase shift.

7. A non-SMB process according to claim 1, wherein the flow rate of fluid that circulates in a given zone is kept approximately constant.

8. A non-SMB process according to claim 1, wherein said shiftings are carried out in the same direction as that of the flow in the loop.

9. A non-SMB process according to claim 1, wherein at least one flow rate of fluid that circulates in an injection line or draw-off line is controlled by the pressure in the device, and preferably the flow rate of fluid that is drawn off as raffinate and/or extract.

10. A non-SMB process according to claim 1, wherein the eluant is a liquid, a supercritical or subcritical fluid, or a compressed gas.

11. A non-SMB process according to claim 1, wherein the number of columns is less than 8.

12. A non-SMB process according to claim 1, wherein the loop comprises four chromatographic zones.

13. A non-SMB process according to claim 1, wherein the number of columns is temporarily zero in one or more chromatographic zones.

14. A non-SMB process of claim 1, wherein at the end of said period all of the injection and draw-off points are shifted by one column or column section in a given direction that is defined relative to that of the flow of a main fluid that circulates through the loop.

15. A non-SMB process of claim 1, wherein said loop is an open loop.

16. A non-SMB process according to claim 15, wherein the succession of the following stages is carried out at least once:

At moment t1 during said period, in a given direction, the position of the injection point or draw-off point is shifted relative to at least one zone by a column or column section, then at a moment t2 during said period, the position of the injection point or draw-off point that is relative to at least one other zone is shifted in the same direction by a column or column section, and the operation is repeated if necessary such that after said time period, the same column configuration or column section configuration as the initial configuration is regained with a shifting of all of the positions of the injection points and draw-off points of the same number of columns or column sections.

17. A non-SMB process according to claim 15, wherein the succession of the following stages is carried out at least once:

At moment t1 during said period, in a given direction, the position of the injection point or draw-off point is shifted relative to at least one zone by a column or column section, in such a way as to increase the length of said zone and to reduce the length of the zone that is adjacent to said zone, then at a moment t2 during said period, the position of an injection point or draw-off point that is relative to at least one other zone is shifted in the same direction by a column or column section, in such a way as to increase the length of said other zone and to reduce the length of the zone that is adjacent to said other zone, and the operation is repeated if necessary such that after said time period, the same column configuration or column section configuration as the initial configuration is regained with a shifting of all of the positions of the injection points and draw-off points of the same number of columns or column sections.

18. A non-SMB process according to claim 15, wherein at moment t1, the position of the extract draw-off point and the position of the raffinate draw-off point are shifted by a column or column section, then at a moment t2 during said period, the position of the feedstock injection point and the position of the eluant injection point are shifted by a column or column section.

19. A non-SMB process according to claim 15, wherein during the period, all of the shiftings of injection positions or draw-off positions are carried out with a time phase shift that is approximately constant and advantageously with a phase shift that is at least equal to one quarter-period.

20. A non-SMB process according to claim 15, wherein during the period, shiftings of the positions of the injection points or draw-off points are carried out with a non-constant time phase shift.

21. A non-SMB process according to claim 15, wherein the flow rate of fluid that circulates in a given zone is kept approximately constant.

22. A non-SMB process according to claim 15, wherein said shiftings are carried out in the same direction as that of the flow in the loop.

23. A non-SMB process according to claim 15, wherein at least one flow rate of fluid that circulates in an injection line or draw-off line is controlled by the pressure in the device, and preferably the flow rate of fluid that is drawn off as raffinate and/or extract.

24. A non-SMB process according to claim 15, wherein the eluant is a liquid, a supercritical or subcritical fluid, or a compressed gas.

25. A non-SMB process according to claim 15, wherein the number of columns is less than 8.

26. A non-SMB process according to claim 15, wherein the loop comprises four chromatographic zones.

27. A non-SMB process according to claim 15, wherein the number of columns is temporarily zero in one or more chromatographic zones.

28. A non-SMB process of claim 15, wherein at the end of said period all of the injection and draw-off points are shifted by one column or column section in a given direction that is defined relative to that of the flow of a main fluid that circulates through the loop.

29. A non-simulated-moving-bed (non-SMB) process for separating at least one component of a mixture that contains it, comprising introducing said mixture into a non-SMB device that has a set of chromatographic columns or chromatographic column sections that contain an adsorbent and are arranged in series and in a loop, whereby the loop comprises at least one feedstock injection point, a raffinate draw-off point, an eluant injection point, and an extract draw-off point, in which a chromatographic zone is determined between an injection point and a draw-off point or vice-versa, and wherein at the end of a given period of time all of the injection and draw-off points are shifted by the same number of columns or column sections, and during said period, shifting different injection and draw-off points at different times such that the lengths of the zones that are defined by said different points are variable.