Abstract: A flow-through ion exchange medium comprising a monolithic stationary phase having interconnecting pores defined by pore walls, and fine ion exchange polymeric layering particles irreversibly bound directly or indirectly to the pore walls, and methods of making such medium and its use on chromatographic separators.

Abstract: A flow-through electrochemical cell assembly with a disposable working electrode structure, including (a) a perimeter wall defining a sample flow channel including an inlet and an outlet, (b) a sample inlet line in fluid communication with the sample flow channel inlet, (c) a sample outlet line providing fluid communication between the sample flow channel outlet and a remote reference electrode, and (d) a disposable working electrode structure comprising an electrically conductive and electrochemically active working electrode region bound as a layer, directly or indirectly, to an electrically insulating substrate surface. The substrate surface is in fluid-sealing relationship with the sample flow channel, and the working electrode region is in fluid communication with said sample flow channel. The working electrode is vapor deposited, directly or indirectly, onto the organic polymer substrate through a mask, and a fluid seal is formed between said working electrode region and perimeter wall.

Abstract: An apparatus for removing charged contaminants from a water stream. The apparatus can be figured to provide the decontaminated water stream to an analytical system. Methods of use of the same are also disclosed.

Abstract: Method and apparatus for suppressed ion analysis in which a sample solution of analyte (e.g., anion) in an eluent of electrolyte counterions (e.g., sodium), is chromatographically separated. Then, the counterions are suppressed in a suppression zone and removed and used to convert the analyte ions to salt form in a salt-converting zone. The suppression and salt-converting zones may be contiguous or remote, and may be performed in devices of the membrane suppresser type. Thereafter, the salts or acids or bases formed from them (e.g., in membrane suppressor devices) are detected. Also, salt conversion can be performed using two ion exchange packed bed salt convertors in which one bed is on-line while the other is regenerated, followed by a reversal of flow.

Abstract: A flow-through electrochemical cell assembly with a disposable working electrode structure, including (a) a perimeter wall defining a sample flow channel including an inlet and an outlet, (b) a sample inlet line in fluid communication with the sample flow channel inlet, (c) a sample outlet line providing fluid communication between the sample flow channel outlet and a remote reference electrode, and (d) a disposable working electrode structure comprising an electrically conductive and electrochemically active working electrode region bound as a layer, directly or indirectly, to an electrically insulating substrate surface. The substrate surface is in fluid-sealing relationship with the sample flow channel, and the working electrode region is in fluid communication with said sample flow channel. The working electrode is vapor deposited, directly or indirectly, onto the organic polymer substrate through a mask, and a fluid seal is formed between said working electrode region and perimeter wall.

Abstract: Method and apparatus for suppressed ion analysis in which a sample solution of analyte (e.g., anion) in an eluent of electrolyte counterions (e.g., sodium), is chromatographically separated. Then, the counterions are suppressed in a suppression zone and removed and used to convert the analyte ions to salt form in a salt-converting zone. The suppression and salt-converting zones may be contiguous or remote, and may be performed in devices of the membrane suppresser type. Thereafter, the salts or acids or bases formed from them (e.g., in membrane suppressor devices) are detected. Also, salt conversion can be performed using two ion exchange packed bed salt convertors in which one bed is on-line while the other is regenerated, followed by a reversal of flow.

Abstract: An acid or base is generated in an aqueous solution by the steps of:

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.

Abstract: An apparatus for removing charged contaminants from a water stream. The apparatus can be figured to provide the decontaminated water stream to an analytical system. Methods of use of the same are also disclosed.

Abstract: An electrolytic suppressor including (a) packing (a suppressor bed of ion exchange resin or a flow-through monolith), (b) an electrode chamber adjacent the suppressor, (c) a first electrode in the electrode chamber, (d) a barrier separating the packing from the first electrode chamber preventing significant liquid flow but permitting transport of ions only of the same charge as the packing, (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. Charged transverse partitions with openings may be included to create a serpentine liquid path.

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.

Abstract: An electrolytic method is provided for purifying an aqueous eluent stream comprising an electrolyte and suitable for use as a chromatography eluent, the electrolyte comprising selected ions of one charge, positive or negative, including at least one contaminant ion of opposite charge. 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.

Abstract: A flow-through electrochemical cell assembly with a disposable working electrode structure, including (a) a perimeter wall defining a sample flow channel including an inlet and an outlet, (b) a sample inlet line in fluid communication with the sample flow channel inlet, (c) a sample outlet line providing fluid communication between the sample flow channel outlet and a remote reference electrode, and (d) a disposable working electrode structure comprising an electrically conductive and electrochemically active working electrode region bound as a layer, directly or indirectly, to an electrically insulating substrate surface. The substrate surface is in fluid-sealing relationship with the sample flow channel, and the working electrode region is in fluid communication with said sample flow channel. The working electrode is vapor deposited, directly or indirectly, onto the organic polymer substrate through a mask, and a fluid seal is formed between said working electrode region and perimeter wall.

Abstract: 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.

Abstract: 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.

Abstract: For anion analysis, the method includes: (a) flowing an aqueous liquid sample stream containing anions to be detected and cation hydroxide through a separator bed, (b) flowing the aqueous effluent from the separator bed through a 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 a 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.

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.

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.

Abstract: Method and apparatus for suppressed ion analysis in which a sample solution of analyte (e.g., anion) in an eluent of electrolyte counterions (e.g., sodium), is chromatographically separated. Then, the counterions are suppressed in a suppression zone and removed and used to convert the analyte ions to salt form in a salt-converting zone. The suppression and salt-converting zones may be contiguous or remote, and may be performed in devices of the membrane suppresser type. Thereafter, the salts or acids or bases formed from them (e.g., in membrane suppressor devices) are detected. Also, salt conversion can be performed using two ion exchange packed bed salt convertors in which one bed is on-line while the other is regenerated, followed by a reversal of flow.

Abstract: A method and apparatus for increasing the current efficiency of suppressor and suppress-like pretreatment devices is disclosed for the purpose of suppressing a high concentration of eluent without the detrimental effects of excess heat generation. The method and apparatus may be used in ion chromatography.