Huron Tech Corp.

Veolia North America Regeneration Services, LLC

Huron Tech Canada, Inc.

John R Jackson

Stephen W Moran

Timothy J Gallivan

Richard E Loftfield

Charles L Pitzer

Dennis F Dong

Derek J Rogers

Alan K Richards

Timothy A Mumby

Mark Ullmann

Sam A Pirapakaran

Charles O Buckingham

A method for recovering a distillable, anhydrous methane-sulfonic acid (MSA) liquid phase from an anhydrous 2-phase gas-liquid mixture wherein the anhydrous 2-phase gas-liquid mixture is generated by sulfonating methane (CH) with sulfur trioxide (SO) in an MSA-forming reactor, or reactor system, according to a radical chain reaction wherein the method comprises (i) separating the gas phase from the liquid phase, (ii) passing the separated liquid phase into a stripping column, and (iii) recovering the stripped anhydrous liquid phase.

Method for removing SOand CHfrom mixtures which contain methane sulfonic acid

Peroxydisulfuric acid and salts thereof are produced electrochemically from an aqueous acid sulfate solution in a cascading series of bipolar electrolytic cells having a cell body frames of polyvinyl chloride which are bonded with a vinyl ester polymer. An aqueous solution of peroxydisulfuric acid and salts thereof are withdrawn from the anode compartment of the last cell in the series, and metal impurities are removed by treatment with an ion exchange resin. Hydrogen peroxide is produced by hydrolyzing persulfuric acid and salts thereof. The sulfuric acid produced is recycled to the first cell in the series of cascading electrolytic cells.

Electrolysis cell and electrodes

An electrochemical process for the production of a hydroxide solution and a sulfate by the electrolysis of a waste aqueous mixture of oxidizable sulfur impurities in the anode compartment of at least one electrolytic cell while producing a hydroxide solution in the cathode compartment of the cell. The process is particularly applicable to the treatment of spent caustic solutions obtained by scrubbing a hydrocarbon process stream contaminated with oxidizable sulfur impurities. The electrolytic cell used in the electrolysis process of the invention can use either a porous membrane or a cationic permselective membrane to separate the anode and cathode compartments of the electrolysis cell. The electrolysis cell can be monopolar or bipolar and when bipolar, the bipolar electrodes if dissimilar, or the respective anode and cathode current collectors if dissimilar, which are attached thereto, are electrically connected by bonding with a conductive polymer or are joined by welding with or without an intermediate metal layer therebetween. Control of pH in the anolyte compartment of the electrolytic cell can be achieved by passing a selected amount of catholyte to the anolyte compartment. Pre-treatment with oxygen produced in the anolyte compartment of the cell avoids release of gaseous products from the anolyte compartment and increases process efficiency. Where the process is conducted in multiple electrolytic cells, such cells are hydraulically connected in a cascading series.

Electrolytic process for treating aqueous waste streams

A monopolar or bipolar filter press electrolyzer. The bipolar filter press electrolyzer can contain a bipolar electrode consisting of a planar metal anode and planar metal cathode electrically connected to respective planar current collectors which can be electrically connected by welding either directly or through an intermediate metal layer different than said metal anode or cathode, or by adhesive bonding utilizing an electrically conductive adhesive. The cell frames can be a molded thermoplastic polymer or laminated thermoplastic or thermosetting polymer sheets. The bipolar electrode assemblies can include at least a pair of thermoplastic or thermosetting cell frame units which can be assembled with either a single gasket or a polymer adhesive.

Filter press electrolyzer

Pulping chemicals and hemicellulose are recovered from a starting solution essentially free of lignin but containing a mixture of hemicellulose and caustic by electrolyzing this solution in the anolyte compartment of an electrolytic cell. By electrolysis, the concentration of caustic in the anolyte is decreased and the concentration of caustic in a catholyte of said cell is increased so as to allow recovery of about 60 to about 80 percent of the caustic present in the hemicellulose caustic starting solution.

Electrolysis process for removal of caustic in hemicellulose caustic

An electrolytic cell and process for the cogeneration of a peroxy acid and salts thereof in an anolyte compartment of the cell and hydrogen peroxide at a desired ratio of an alkali metal hydroxide to hydrogen peroxide in the catholyte compartment of the cell. An ammonium compound is present as a reactant in the catholyte compartment. Ammonia is recycled from the catholyte compartment of the cell to the anolyte compartment of the cell or removed as a product.

Co-generation of ammonium persulfate anodically and alkaline hydrogen

Pulping chemicals and hemicellulose are recovered from a starting solution essentially free of lignin but containing a mixture of hemicellulose and caustic by electrolyzing this solution in the anolyte compartment of an electrolytic cell. By electrolysis, the concentration of caustic in the anolyte is decreased and the concentration of caustic in a catholyte of said cell is increased so as to allow recovery, of about 60 to about 80 percent of the caustic contained in the hemicellulose caustic starting solution.

A process is disclosed for producing a dilute solution of an alkali or alkaline earth metal chlorate from a chlorine and carbon dioxide waste gaseous stream. The process of the invention can be combined in a continuous process for the production of an alkali or alkaline earth metal chlorate for use in a chlorine dioxide generator for the production of chlorine dioxide in which the waste gaseous stream from the chlorine dioxide generator is converted to a dilute solution of an alkali or alkaline earth metal chlorate and passed to an electrochemical cell for the generation of an alkali or alkaline earth metal sodium chlorate, the product of the electrochemical cell being in turn passed to the chlorine dioxide generator.

Method for the preparation of chlorates from waste gas streams obtained

A method has been devised for removing chromium ions from a chromium ion containing liquid and recovering chromium oxide in a usable form by (a) adjusting the temperature of the liquid to an optimal temperature to maximize reduction and simultaneous precipitation of the chromium oxide; (b) adding a reducing agent to the liquid to form a mixture, where the reducing agent is at least one inorganic sulfur compound selected from the group of sulfur compounds where sulfur is in the 4.sup.+ oxidation state; and (c) adjusting the pH of the mixture to a pH between 5 and 7; (d) optionally further adjusting the pH of the mixture to a pH between above 7 to 12; and (e) separating the chromium from the mixture.

Process for chromium removal using an inorganic sulfur compound

An integrated process for the production of alkali or alkaline earth metal chlorates and chlorine dioxide in which the chromium compound impurities in the alkali or alkaline earth metal chlorate aqueous solution produced by an electrochemical cell are removed and recycled to the electrochemical cell; a substantially chromium compound free alkali or alkaline earth metal chlorate is converted to chlorine dioxide and by-products; and the by-products are converted to substantially chlorine-free carbon dioxide, which is vented, and a dilute solution of an alkali or alkaline earth metal chlorate, which is recycled to the electrochemical cell.

Integrated process for the production of alkali and alkaline earth metal

A method has been devised for removing chromium ion from a chromium ion containing liquid and recovering chromium oxide in an usable form by (a) adjusting the temperature of the liquid to an optimal temperature to maximize reduction and simultaneous precipitation of the chromium oxide; (b) adding a reducing agent to the liquid to form a mixture, where the reducing agent is at least one inorganic sulfur compound selected from the group of sulfur compounds where sulfur is in the 4.sup.+ oxidation state and (c) adjusting the pH of the mixture to a pH between 5 and 7.

A process for precipitating and removing chromium compounds in which chromium is in the hexavalent state from aqueous liquids, particularly, alkaline earth metal or alkali metal chlorate-rich solutions containing chloride, chlorate, and bichromate ions produced by the electrolysis of brine. In the process, hydroxylamine, hydroxylamine sulfate, hydroxylamine formate or hydroxylamine hydrochloride is used as a reducing agent to react and co-precipitate at a neutral or acid pH with hexavalent chromium ions present in the aqueous liquid, the reaction and precipitation taking place, generally, at a pH of about 4.0 to about 6.5 and, a temperature of about 50.degree. C. to about 100.degree. C. Precipitated oxides and hydroxides of divalent and trivalent chromium can be removed, for instance, by filtration. Reaction time to achieve a level of about 10 parts per million or less of chromium ions in the filtrate varies from less than about 5 hours to less than about 1 hour depending upon selection of reaction temperature and reaction pH. For instance, to achieve a level of 2 parts per million or less chromium ion after removal of the precipitate formed during the reaction at a pH of 5.0-5.5, a reaction time of 10 minutes at a temperature of 90.degree.-95.degree. C. is required. A reaction time of 30 minutes at a temperature of 70.degree. C. or 120 minutes at a temperature of 60.degree. C. provides a similar level of chromate ion removal.

Growing community of inventors

Wilmington, NC, United States of America

John R Jackson