Large capacity acid or base generator and method of use

Patent metadata

Field	Value
Publication number	US-9645124-B2
Application number	US-201313738632-A
Country	US
Kind code	B2
Filing date	Jan 10, 2013
Priority date	Feb 2, 1998
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

Method and apparatus for generating an acid or base, e.g. for chromatographic analysis of anions. For generating a base the method includes the steps of providing a cation source in a cation source reservoir, flowing an aqueous liquid stream through a base generation chamber separated from the cation source reservoir by a barrier (e.g. a charged membrane) substantially preventing liquid flow while providing a cation transport bridge, applying an electric potential between an anode cation source reservoir and a cathode in the base generation chamber to electrolytically generate hydroxide ions therein and to cause cations in the cation source reservoir to electromigrate and to be transported across the barrier toward the cathode to combine with the transported cations to form cation hydroxide, and removing the cation hydroxide in an aqueous liquid stream as an effluent from the first base generation chamber. Suitable cation sources include a salt solution, a cation hydroxide solution or cation exchange resin.

First claim

The invention claimed is:

1. An eluent generator for generating an acid or a base comprising:
(a) an ion source reservoir;
(b) a remote reservoir for holding a solution comprising one of a cation-containing solution or an anion-containing solution, the remote reservoir supplying the solution to the ion source reservoir;
(c) an acid or base generation chamber having an inlet port and an outlet port, the outlet port of the acid or base generation chamber configured to be fluidically coupled to an inlet of a chromatographic separator;
(d) a charged first barrier disposed between the ion source reservoir and the acid or base generation chamber, the barrier substantially preventing liquid flow while providing an ion transport bridge for only ions of one charge, positive or negative;
(e) a first electrode in electrical communication with the ion source reservoir;
(f) a second electrode in electrical communication with the first acid or base generation chamber;
(g) an aqueous liquid source in fluid communication with the inlet port of the acid or base generation chamber; and
(h) a conduit for recycling solution from an outlet of the ion source reservoir to an inlet of the remote reservoir.

2. The eluent generator of claim 1 further comprising: (i) a pump configured to deliver the solution from the remote reservoir to the ion source reservoir.

3. The eluent generator of claim 1 , wherein during operation of the eluent generator, the acid or base generation chamber outputs acid or base at about 1 milliliter per minute.

4. The eluent generator of claim 1 , in which the base outputted from the base generation chamber comprises potassium hydroxide.

5. The eluent generator of claim 1 , further comprising: (j) a power supply for applying an electrical potential between the first and second electrodes.

6. The eluent generator of claim 1 , in which a total volume of the ion source reservoir and the remote reservoir is at least about 5 times a volume of the acid or base generation chamber.

7. The eluent generator of claim 1 , in which the ion source reservoir does not contain an ion exchange resin.

8. A chromatography system to analyze a liquid sample containing components of interest comprising:
(a) an ion source reservoir;
(b) a remote reservoir holding a solution comprising one of a cation-containing solution or an anion-containing solution, the remote reservoir supplying the solution to the ion source reservoir;
(c) an acid or base generation chamber having an inlet port and an outlet port;
(d) a charged first barrier disposed between the ion source reservoir and the acid or base generation chamber, the barrier substantially preventing liquid flow while providing an ion transport bridge for only ions of one charge, positive or negative;
(e) a first electrode in electrical communication with the ion source reservoir;
(f) a second electrode in electrical communication with the first acid or base generation chamber; and
(g) an aqueous liquid source in fluid communication with the inlet port of the acid or base generation chamber;
(h) a sample injection port for injecting the liquid sample containing components of interest;
(i) a chromatographic separator for separating the components of interest, an inlet port of the chromatographic separator being in fluid communication with the sample injection port and the outlet port of the acid or base generation chamber, whereby a chromatography effluent exits from an outlet port of the chromatographic separator;
(j) a detector in fluid communication with the chromatographic separator for detecting the separated components of interest in the chromatographic effluent; and
(k) a conduit for recycling solution from an outlet of the ion source reservoir to an inlet of the remote reservoir.

9. The chromatography system of claim 8 , in which the detector comprises a conductivity detector.

10. The chromatography system of claim 8 , in which a total volume of the ion source reservoir and the remote reservoir is at least about 5 times a volume of the acid or base generation chamber.

11. The chromatography system of claim 8 further comprising: (l) a pump configured to deliver the solution from the remote reservoir to the ion source reservoir.

12. The chromatography system of claim 8 , further comprising: (m) a power supply for applying an electrical potential between the first and second electrodes.

Assignees

• Dionex Corp

Inventors

• Liu Yan
• Small Hamish
• Avdalovic Nebojsa

Classifications

• Y10T436/25

  including sample preparation · CPC title

• B01D15/426

  Specific type of solvent · CPC title

• G01N30/96 Primary

  using ion-exchange (G01N30/02, G01N30/90 take precedence) · CPC title

• G01N2030/965

  suppressor columns · CPC title

• B01D15/36

  involving ionic interaction, e.g. ion-exchange, ion-pair, ion-suppression or ion-exclusion · CPC title