Ionics, Inc.

Wayne A McRae

Keith James Sims

Russell James MacDonald

Li Zhang

Arthur L Goldstein

Irving D Elyanow

Bruce T Batchelder

William W Carson

Thomas J Susa

Oleg Grebenyuk

Robert J Mandle

Hilda R Zanapalidou

An improved apparatus and operating method related thereto for deionizing water to produce substantially pure water using electric field and ion exchange materials are disclosed, including embodiments incorporating one or more of the novel features of brine and electrode streams flowing in a direction counter-current to the stream being deionized, a filling of the brine stream with stratified ion exchange materials, a stream mixing feature for mixing the stream being deionized, a gas removal feature for removal of gases, a spiral-wound embodiment of an electrodialysis device according to the invention, and a method for determining the preferred operating current for electrodialysis systems according to this invention.

Device and method for electrodialysis

Improved electrodialysis (ED) stacks are disclosed having one or more components selected from the group:

Electrodialysis including filled cell electrodialysis

Improved electrodialysis (ED) stacks are disclosed having one or more components selected from the group: a) cation exchange membranes having ion exchange groups predominantly sulfonic acid groups and a minor amount of weakly acidic and/or weakly basic groups or membranes which are selective to monovalent cations and simultaneously therewith, cation exchange granules selective to monovalent cations as packing in the dilute compartments; b) anion exchange membranes having as ion exchange groups only quaternary ammonium and/or quaternary phosphonium groups and substantially no primary, secondary and/or tertiary amine and/or phosphine groups or membranes which are selective to monovalent anions simultaneously therewith, anion exchange granules selective to monovalent anions as packing in the dilute compartments; c) as packing in the dilute compartment, anion exchange granules which are selective to monovalent anions, or cation exchange granules which are selective to monovalent cations, or cation exchange granules having as exchange groups a predominant amount of sulfonic acid groups and a minor amount of weakly acidic and/or weakly basic groups, or anion exchange granules consisting of organic polymers having as anion exchange groups only quaternary ammonium and/or quaternary phosphonium groups and almost no primary, secondary and/or tertiary amine and/or phosphine groups.

Electrodialysis ('ED') stacks are disclosed having components selected from the group:

Apparatus for measuring the concentration of carbon compounds in water, the apparatus including a reaction zone for converting such carbon compounds to free and/or combined carbonaceous acids, a device for introducing at least a portion of the water to be analyzed as liquid or vapor into such zone, a device for contacting such acids with weakly basic anion exchange resin and a device for measuring the electrical impedance of at least a portion of such resin.

Carbon monitor containing anion exchange resin

Novel thin film composite membranes are disclosed. They are prepared from vinyl and related monomers by phase transfer catalysis at the interface between one phase containing a polymerizable vinyl or related monomer and a second phase containing an entity necessary to initiate polymerization of the monomer. The two phases are substantially insoluble in each other. At least one of the phases is a fluid. One of the phases is integral with a porous support or substrate or a precursor of such support or substrate such as a porous organic or inorganic diaphragm made by thermal phase inversion from which the soluble phase has not been extracted.

Thin film composite membranes from vinyl and related nomomers

A process is disclosed for recovering renatured polypeptides and proteins (collectively 'polypeptides') from solution thereof and/or of their S-sulfonate derivatives (collectively 'solution of polypeptides') in denaturants comprising:

Renaturing reversibly denatured polypeptides and proteins by

An improved integrated and cyclic process and apparatus are disclosed wherein portions of various process and waste fluids are recycled to control impurities in the influents to membrane chlor-alkali cells and simultaneously to minimize liquid pollutants from the process. The improved process and apparatus reduces energy costs and wastes while simultaneously controlling impurities important to operation of membrane chlor-alkali electrolytic cells.

Process and apparatus for controlling impurities and pollution from

An improved process and apparatus for pH control in the anode compartments of membrane chlor-alkali cells is disclosed wherein an anode is used having an oxygen evolution efficiency substantially equivalent chemically to the hydroxide ion transfer efficiency of the membrane.

Method and apparatus for controlling anode pH in membrane chlor-alkali

An improved process and apparatus for pH control and energy savings in chlor-alkali electrolysis cells is disclosed wherein a fuel cell type spaced porous catalytic anode is utilized to chemically oxidize a controlled, sub stoichiometric amount of hydrogen to provide hydrogen ions to a recirculating anolyte. The pH is monitored and the flow of hydrogen fuel adjusted to provide a resultant desired pH in the range of about 2 to about 4. Optionally, hydrogen gas produced at the cell cathode may comprise the fuel supply and a spaced porous catalytic cathode may be employed for hydrogen supply control and depolarization.

Process for chloro-alkali electrolysis cell

An improved process and apparatus for pH control and energy savings in chlor-alkali electrolyis cells is disclosed wherein a fuel cell type spaced porous catalytic anode is utilized to chemically oxidize a controlled, sub stoichiometric amount of hydrogen to provide hydrogen ions to a recirculating anolyte. The pH is monitored and the flow of hydrogen fuel adjusted to provide a resultant desired pH in the range of about 2 to about 4. Optionally, hydrogen gas produced at the cell cathode may comprise the fuel supply and a spaced porous catalytic cathode may be employed for hydrogen supply control and depolarization.

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Mannedorf, Switzerland

Wayne A McRae