Aqueous stream purifier and method of use
AssigneeDionex Corporation
InventorsKannan Srinivasan, Nebojsa Avdalovic
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Abstract
An electrolytic method is provided for purifying an aqueous stream, including at least one contaminant ion. In one embodiment, the eluent stream flows through a purifying flow channel, including ion exchange bed, an electric field is applied through the flowing eluent stream in the purifying flow channel, and the contaminant ion is removed from the eluent stream. In another embodiment, no electric field is applied and the ion exchange bed is periodically regenerated. Two beds may be used with one bed on line while the other bed is regenerated followed by a reversal of flow.
Claims16
A method for purifying an aqueous stream, said aqueous stream including at least one contaminant ion, said method comprising.
- (a) flowing said aqueous stream through flow-through ion exchange medium having exchangeable ions of the same charge as said contaminant ion in a first purifying flow channel having an inlet and an outlet,
- (b) removing said contaminant ion from said aqueous stream in said flow channel to produce a purified aqueous stream which flows out said flow channel outlet,
- (c) discontinuing the flow of said aqueous stream through first purifying flow channel,
- (d) directing said aqueous stream through flow-through ion exchange medium haying exchangeable ions of the same charge as said contaminant ion in a second purifying flow channel, and
- (e) regenerating the ion exchange medium in said first purifying flow channel by flowing an aqueous regenerant solution therethrough.
A method for purifying an aqueous stream and suitable for use as a chromatography eluent, said aqueous stream including at least one contaminant ion, said method comprising
- (a) flowing said aqueous stream through flow-through first ion exchange medium having exchangeable ions of the same charge as said contaminant ion in a purifying flow channel having an inlet and an outlet,
- (b) removing said contaminant ion from said eluent stream in said purifying flow channel to produce a purified aqueous stream which flows out said purifying flow channel outlet,
- (c) flowing a first liquid sample stream analyte of the same charge as said contaminant ion and said purified aqueous stream from said purifying flow channel through chromatography separation medium having exchangeable ions of the same charge as said contaminant ion, and
- (d) after completion of step (c), and before flow of a second liquid sample stream through said chromatography separation medium, regenerating said ion exchange medium in said purifying flow channel by flowing an aqueous regenerant liquid stream through said purifying flow channel.
Chromatography apparatus comprising:
- (a) at least one contaminant ion-purifying housing defining at least one purifying flow channel having an inlet an outlet,
- (b) a source of an aqueous liquid stream including at least one contaminant ion in liquid communication with said purifying flow channel inlet,
- (c) spaced first and second electrodes of opposite charge disposed to apply an electric field through said one purifying flow channel, and
- (d) chromatographic separation medium having an inlet and an outlet, with exchangeable ions of the same charge as said contaminant ion, positive or negative, said separation medium inlet being in liquid communication with said one purifying flow channel outlet.
Chromatography apparatus comprising:
- (a) a source of aqueous liquid comprising at least one contaminant ion,
- (b) at least one contaminant ion-purifying housing defining at least one purifying flow channel,
- (c) first flow-through ion exchange medium, having exchangeable ions of one charge, positive or negative of the same charge as said contaminant ion, disposed in said one purifying flow channel,
- (d) chromatographic separation medium having an inlet and an outlet, with exchangeable ions of the same charge as first flow-through ion exchange medium, said separation medium inlet being in liquid communication with said one purifying flow channel,
- (e) a source of regenerant solution, and
- (f) valving including at least a first and second position, permitting, in said first position, flow from said one purifying flow channel to said chromatographic separation medium but blocking flow from said regenerant source to said one purifying flow channel and permitting, in said second position, flow from said regenerant solution source to said one purifying flow channel but blocking flow from said one purifying flow channel to said chromatographic separator.
Dependencies are inferred from the claim text.