Method of ion chromatography wherein a specialized electrodeionization apparatus is used
AssigneeTrovion Singapore Pte. Ltd., Co.
InventorJohn Riviello
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Abstract
The present invention pertains to a method of ion chromatography wherein a specialized electrodeionization (EDI) apparatus is used for (1) the preparation of a pure acid or pure base for use as an eluent in a chromatographic separation column and/or (2) for ion suppression (or neutralization) of the acid or base after it has been used to elute ions from a chromatographic separation column. Methods for trace ion removal, acid and base neutralization, and ion suppression using a specialized EDI apparatus are also described. The methods described herein allow for the ion suppression of samples containing chloride, nitrate, and other electrochemically active anions, without causing damage to the suppressor.
Claims61
A method of ion chromatography for the analysis of an anion sample, comprising:
- (a) flowing a basic solution through a homogeneous anion depletion chamber of a CEDI apparatus to remove trace anion impurities to generate a pure basic solution, followed by;
- (b) flowing the pure basic solution through a chromatographic separator column, which contains the anion sample, to elute the anion sample, followed by;
- (c) flowing the pure basic solution containing the anion sample through a homogeneous cation depletion chamber of the CEDI apparatus to suppress the basic solution by converting the basic solution to water, and to enhance the anion sample by converting the anion to an acid;
- and
- (d) flowing the water and acid generated in the homogeneous cation depletion chamber through an electrical conductivity detector to analyze the anion sample in the acid form.
A method of ion chromatography for the analysis of a cation sample, comprising:
- (a) flowing an acidic solution through a homogeneous cation depletion chamber of a CEDI apparatus to remove trace cation impurities to generate a pure acidic solution, followed by;
- (b) flowing the pure acidic solution through a chromatographic separator column, which contains the cation sample, to elute the cation sample, followed by;
- (c) flowing the pure acidic solution containing the cation sample through a homogeneous anion depletion chamber of the CEDI apparatus to suppress the acidic solution by converting the acidic solution to water, and to enhance the cation sample by converting the cation to a base;
- and
- (d) flowing the water and base generated in the homogeneous anion depletion chamber through an electrical conductivity detector to analyze the cation sample in the base form.
A method of trace anion removal from a base, comprising flowing a base containing trace anions through a homogeneous anion depletion chamber of a CEDI apparatus.
A method of trace cation removal from an acid, comprising flowing an acid containing trace cations through a homogeneous cation depletion chamber of a CEDI apparatus.
A method of simultaneous trace anion removal from a base and trace cation removal from an acid, comprising:
- (a) flowing a base containing trace anions through a homogeneous anion depletion chamber of a CEDI apparatus;
- and
- (b) flowing an acid containing trace cations through a homogeneous cation depletion chamber of the CEDI apparatus of step (a).
A method of acid neutralization, comprising flowing an acid through a homogeneous anion depletion chamber of a CEDI apparatus.
A method of base neutralization, comprising flowing a base through a homogeneous cation depletion chamber of a CEDI apparatus.
A method of simultaneous acid neutralization and base neutralization, comprising:
- (a) flowing an acid through a homogeneous anion depletion chamber of a CEDI apparatus;
- and
- (b) flowing a base through a homogeneous cation depletion chamber of the CEDI apparatus of step (a).
A method of anion suppression, comprising flowing a base containing an anion sample of interest through a homogeneous cation depletion chamber of a CEDI apparatus.
A method of cation suppression, comprising flowing an acid containing a cation sample of interest through a homogeneous anion depletion chamber of a CEDI apparatus.
A method of simultaneous anion suppression and cation suppression, comprising:
- (a) flowing a base containing an anion sample of interest through a homogeneous cation depletion chamber of a CEDI apparatus;
- and
- (b) flowing an acid containing a cation sample of interest through a homogeneous anion deletion chamber of the CEDI apparatus of step (a).
Dependencies are inferred from the claim text.