摘要:
A combination electrolytic suppressor and separate eluent generator and method. The suppressor includes a chromatography effluent flow channel, an ion receiving flow channel, and a first suppressor ion exchange barrier therebetween permeable to electrolyte ions but not liquid flow. The effluent from the chromatography effluent compartment flows through the detector, the ion receiving channel, and to an eluent generator. The generator includes a first generator electrode in a first generator electrode chamber, an electrolyte ion reservoir, a first charged generator barrier separating the first eluent generator electrode chamber from the electrolyte ion reservoir, preventing liquid flow but permitting transport of said electrolyte ions, and a second generator electrode on the opposite side of the first generator barrier from the first generator electrode. Fluid flows from the ion receiving flow channel past the second generator electrode. Acid or base electrolytically generated in the first generator electrode chamber flows as an eluent stream to the chromatographic separator.
摘要:
An electrolyitic suppressor including (a) a suppressor bed of ion exchange resin, (b) an electrode chamber adjacent the suppressor, (c) a first electrode in the electrode chamber, (d) a barrier separating the suppressor bed from the first electrode chamber preventing significant liquid flow but permitting transport of ions only of the same charge as the suppressor bed resin, (e) a second electrode in electrical communication with the resin bed, and (f) a recycle conduit between the suppressor outlet port and said electrode chamber. The second electrode may be in contact with the ion exchange resin in the suppressor or located in second electrode chamber. For anion analysis, the method of using the apparatus includes: (a) flowing an aqueous liquid sample stream containing anions to be detected and cation hydroxide through the separator bed, (b) flowing the aqueous effluent from the separator bed through the flow-through suppressor, (c) flowing the effluent liquid from the suppressor past a detector, (d) recycling said liquid effluent from the detector through a cathode chamber proximate to the suppressor bed and separated by the first barrier, and (e) applying an electrical potential between the cathode and the anode. Water is electrolyzed at the anode to cause cations on the cation exchange resin to electromigrate toward the barrier and to be transported across the barrier toward the cathode while water in the cathode chamber is electrolyzed to generate hydroxide ions which combine with the transported cations to form cation hydroxide in the cathode chamber.
摘要:
An electrolyitic suppressor including (a) a suppressor bed of ion exchange resin, (b) an electrode chamber adjacent the suppressor, (c) a first electrode in the electrode chamber, (d) a barrier separating the suppressor bed from the first electrode chamber preventing significant liquid flow but permitting transport of ions only of the same charge as the suppressor bed resin, (e) a second electrode in electrical communication with the resin bed, and (f) a recycle conduit between the suppressor outlet port and said electrode chamber. The second electrode may be in contact with the ion exchange resin in the suppressor or located in second electrode chamber. For anion analysis, the method of using the apparatus includes: (a) flowing an aqueous liquid sample stream containing anions to be detected and cation hydroxide through the separator bed, (b) flowing the aqueous effluent from the separator bed through the flow-through suppressor, (c) flowing the effluent liquid from the suppressor past a detector, (d) recycling said liquid effluent from the detector through a cathode chamber proximate to the suppressor bed and separated by the first barrier, and (e) applying an electrical potential between the cathode and the anode. Water is electrolyzed at the anode to cause cations on the cation exchange resin to electromigrate toward the barrier and to be transported across the barrier toward the cathode while water in the cathode chamber is electrolyzed to generate hydroxide ions which combine with the transported cations to form cation hydroxide in the cathode chamber.
摘要:
A method for generating high purity acid or base in an aqueous stream for use as an eluent for chromatography and, particularly, ion chromatography. For generating a base for anion chromatography, the aqueous stream is directed through a cation exchange bed having a first strongly acidic and a second weakly acidic portions. An electrical potential is applied to the bed. Cations on the bed electromigrate into the aqueous stream while hydroxide ions are electrolytically generated to form a base-containing eluent. Anions to be detected and the generated eluent flow through a chromatographic separator. The chromatographic effluent flows past a detector.
摘要:
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.
摘要:
An apparatus for generating high purity acid or base in an aqueous stream for use as an eluent for chromatography and, particularly, ion chromatography. For generating a base for anion chromatography, the aqueous stream is directed through a cation exchange bed. An electrical potential is applied to the bed. Cations on the bed electromigrate into the aqueous stream while hydroxide ions are electrolytically generated to form a base-containing eluent. Anions to be detected and the generated eluent flow through a chromatographic separator and a detector. In one embodiment, between separation and detection, the separated anion stream flows through a second cation exchange bed with no electrical potential applied. The second bed serves as a suppressor. After completion of the desired number of cycles, flow through the first and second cation exchange beds may be reversed by appropriate valving for the next sample stream. An electrical potential is applied to the second bed while the potential is discontinued in the first bed. Thus, the second bed generates eluent and the first bed suppresses conductivity of the base. In another embodiment, the second cation exchange bed is disposed after the detector as a sink to retain the cations of the base and the eluent. By appropriate valving, flow may be reversed through the first and second beds with potential applied in the second bed but not the first bed. During the reversal setting of the valving, the second bed generates the base.
摘要:
Disclosed is a method and apparatus for electrolytically generating an acid or base eluent in an aqueous solution and for simultaneously suppressing conductivity of the eluent in an ion exchange bed after chromatographic separation in an ion chromatography system.
摘要:
A continuous electrochemical pump comprising a water generator compartment, an anode compartment on one side of said generator compartment, a cation exchange barrier, separating the generator compartment from the anode compartment, a first electrode in electrical communication with the anode compartment, a cathode compartment adjacent the generator chamber, an anion exchange barrier, separating the generation compartment from the cathode compartment, and a second electrode in electrical communication with the cathode compartment. Use of the pump as a sample concentrator. A feedback loop for the pump. A reservoir, with or without an intermediate piston, on the output side of the pump.
摘要:
A continuous electrochemical pump comprising a water generator compartment, an anode compartment on one side of said generator compartment, a cation exchange barrier, separating the generator compartment from the anode compartment, it first electrode in electrical communication with the anode compartment, a cathode compartment adjacent the generator chamber, an anion exchange barrier, separating the generation compartment from the cathode compartment, and a second electrode in electrical communication with the cathode compartment. Use of the pump as a sample concentrator. A feedback loop for the pump. A reservoir, with or without an intermediate piston, on the output side of the pump.
摘要:
A continuous electrochemical pump comprising a water generator compartment, an anode compartment on one side of said generator compartment, a cation exchange barrier, separating the generator compartment from the anode compartment, a first electrode in electrical communication with the anode compartment, a cathode compartment adjacent the generator chamber, an anion exchange barrier, separating the generation compartment from the cathode compartment, and a second electrode in electrical communication with the cathode compartment. Use of the pump as a sample concentrator. A feedback loop for the pump. A reservoir, with or without an intermediate piston, on the output side of the pump.