Single column closed-loop recycling with periodic intra-profile injection

• US 6,063,284 A
• Filed: 05/15/1997
• Issued: 05/16/2000
• Est. Priority Date: 05/15/1997
• Status: Expired due to Term

• Current Assignee: EMD Chemicals Incorporated (Merck & Co., Inc.)
• Original Assignee: EM Industries, Inc.
• Inventors: Grill, Charles M.
• Primary Examiner(s): Therkorn, Ernest G.
• Application Number:
  US08/857,039
• Time in Patent Office: 1,097 Days
• Field of Search: 210/635, 210/656, 210/659, 210/198.2
• US Class Current: 210/659
• CPC Class Codes: B01D 15/1814 recycling of the fraction to be distributed
• CPC Class Codes: B01D 15/1857 Reactive simulated moving beds
• CPC Class Codes: G01N 30/44 using recycling of the fraction to be distributed

Abstract

A preparative chromatographic cyclical process utilizing a single column comprising, at steady state: (a) establishing and maintaining a circulating chromatographic profile through said column and through one solvent pump; (b) discontinuously and periodically injecting a sample comprising at least two components, into the interior of said maintained circulating profile; and (c) collecting, discontinuously and periodically, at least two enriched fractions from said circulating profile.

Claims

1. A preparative chromatographic closed loop steady state cyclical process utilizing a single column comprising, at steady state conducting the following steps:

a. establishing and maintaining a circulating chromatographic profile through said column and through one solvent pump;

b. discontinuously and at each cycle injecting a sample comprising at least two components, into the interior of said maintained circulating profile of said single column, said injecting being conducted by an injection loop controlled in an inject position by an injection valve so as to inject the sample in the loop into the interior of said circulating profile, said injection valve remaining in the inject position from the time of injection until all of the profile has eluted from the column, and then adjusting the injection valve to a load position to load the injection loop when all the profile is on the column, and

c. collecting, discontinuously and periodically, at least two enriched fractions from said circulating profile.

2. A process according to claim 1, further comprising:

d. through the solvent pump, pumping solvent, as a mobile phase, substantially continuously into the column during a single cycle.

3. A process according to claim 2, further comprising for each steady state cycle:

e. referencing with respect to time all events that occur after the start of collection of a Fraction 1 to the event which comprises the start of said collection of Fraction 1;

f. stopping the solvent pump during the collection of a Fraction 3, such stoppage continuing until the end of the cycle thereby providing reproducible cycles with respect to time.

4. A process according to claim 1, wherein no loss of the circulating profile occurs during the injection onto said maintained circulating profile.