Abstract: Disclosed are devices, systems, and methods for producing broad spectrum disinfectants, sanitizers, cleaner and deodorizers using chlorine dioxide compositions, and more particularly, to methods for producing chlorine dioxide compositions having improved long term stability by the proper choice of pH and through the careful choice of other product formula ingredients.

Abstract: Aqueous solutions of peroxyacids are stabilized by a polymeric stabilizer selected from a phosphino polycarboxylic acid, a poly(acrylic acid)-acrylamidoalkylpropane sulfonic acid co-polymer, or a poly(acrylic acid)-acrylamidoalkylpropane sulfonic acid-sulfonated styrene terpolymer. The polymer-stabilized peroxyacid solutions have applications in aseptic sterilization and disinfecting of surfaces.

Abstract: A chlorine dioxide solution generating apparatus is provided for use primarily in water treatment. The apparatus has a reaction chamber supplied with metered quantities of an acidic solution and a chlorite or chlorate solution whereby a reservoir of a chlorine dioxide solution is generated and retained within the reaction chamber. A conduit is provided along which a pressurized flow of a motive fluid is fed and with which the interior of the reaction chamber communicates via a dip tube. A venturi is located in the conduit adjacent an outlet from the dip tube whereby suction is applied to the reaction chamber by the pressurized flow of motive fluid. The suction draws chlorine dioxide solution from the reservoir whereby it is entrained into the flow of motive fluid. A controller is provided to control flow of motive fluid and metering of the supply of the solutions to the reaction chamber.

Abstract: The invention relates to a process for the production of chlorine dioxide comprising forming chlorine dioxide in a reaction medium in a reaction vessel and withdrawing chlorine dioxide as a gas from the reaction medium in the reaction vessel, the process further comprising adding chlorine dioxide to at least one raw material used in the process. The invention further relates to the use of chlorine dioxide for the reduction of the amount of chlorinated aromatic compounds occurring in a process for the production of chlorine dioxide.

Abstract: Disclosed herein are embodiments of a chlorine dioxide generating system. The system typically includes a reactor having a reactor volume into which sulfuric acid and sodium chlorite are delivered according to Formula 1: (C1)(F1)=C2, wherein F1=flow rate of delivery of sodium chlorite to the at least one reactor, volume/time, C1=amount of CIO2 produced per amount of sodium chlorite delivered to reactor; and C2=CIO2 output amount/time; and wherein said reactor volume and F1 are such so as to provide a contact time between acidifying agent and sodium chlorite in the range of about 0.5 to about 30 minutes.

Abstract: The invention relates to an apparatus (1) for feeding chlorine dioxide to water, comprising a first feed pipe (5a) for feeding in a first reaction component, comprising a second feed pipe (5b) for feeding in a second reaction component, comprising a mixing tube (2) for mixing and reacting the two reaction components to chlorine dioxide, at one end of which the two feed pipes (5a, 5b) join and at the other end of which is arranged a suction chamber (4) into which feed water to be enriched with chlorine dioxide can be sprayed by means of a nozzle (12), and comprising an exit water pipe (13) leading downstream from the suction chamber (4). This object is further to develop such an apparatus so that it is simple and has a robust design and permits different chlorine dioxide syntheses based on two reaction components to be carried out without danger.

Abstract: According to one aspect of the invention, a method of converting an oxy halide salt into a halide dioxide in a reaction zone under certain conditions is provided. More specifically, the method includes generating chlorine dioxide from a stable composition comprising an oxy halide salt by introducing said composition to a reducing agent and minimum temperature within the reaction zone.

Abstract: According to one aspect of the invention, a method of converting an oxy halide salt into a halide dioxide in a reaction zone under certain conditions is provided. More specifically, the method includes generating chlorine dioxide from a stable composition comprising an oxy halide salt by introducing said composition to a reducing agent and minimum temperature within the reaction zone. According to another aspect of the invention, a composition for a stable chlorine dioxide precursor comprising an oxy halide salt is provided.

Abstract: A method of simultaneously cleaning and disinfecting an industrial water system is described and claimed. The method involves the addition to the water of the industrial water system of a Compound selected from the group consisting of the alkali salts of chlorite and chlorate and mixtures thereof; and an acid, followed by allowing the water in the industrial water system to circulate for several hours. The reaction of the alkali salts of chlorite and chlorate and acid produces chlorine dioxide in-situ in the water of the industrial water system. The chlorine dioxide kills microorganisms and the acid acts to remove deposits upon the water-contact surfaces of the equipment. This cleaning and disinfecting method works in a variety of industrial water systems including cooling water systems.

Abstract: Chlorine dioxide (ClO2) is produced by apparatus and methods wherein a ClO2 gas produced in the apparatus is quickly introduced into a fluid stream to be treated with said gas. To this end, the apparatus has an interior chemical reaction chamber which houses an internal fluid flow tube having a fluid impervious upper section and a porous lower section that respectively define two zones within the interior chemical reaction chamber.

Abstract: A storage and mixing device is illustrated and described. The device can include first and second separate containers each defining a distinct internal cavity. The first container can be movable (e.g., rotatable) relative to the second container between a first position and a second position. In the first position, the cavities can be substantially sealed from one another. In the second position, a first gas forming ingredient in one of the cavities can mix with a second gas forming ingredient in the other cavity to form a gas, such as chlorine dioxide gas. The device can have one or more filtered openings to allow gas generated by mixing the first and second gas forming ingredients to escape into the ambient environment.

Abstract: According to one aspect of the invention, a method of converting an oxy halide salt into a halide dioxide in a reaction zone under certain conditions is provided. More specifically, the method includes generating chlorine dioxide from a stable composition comprising an oxy halide salt by introducing said composition to a reducing agent and minimum temperature within the reaction zone. According to another aspect of the invention, a composition for a stable chlorine dioxide precursor comprising an oxy halide salt is provided.

Abstract: Method to prepare fluids (liquids and gases) containing pure chlorine dioxide which is not contaminated by the starting materials or the byproducts of the chlorine dioxide synthesis or to deliver pure chlorine dioxide into any medium capable of dissolving chlorine dioxide, wherein the chlorine dioxide generated in the process is transported across a pore free polymeric membrane via selective permeation into the target medium.

Abstract: The invention relates to a continuous process for the production of chlorine dioxide comprising: —feeding chlorate ions, hydrogen peroxide and an acid into a reactor comprising packing elements inside; —reacting said chlorate ions, hydrogen peroxide and acid in said reactor to form a product stream comprising chlorine dioxide; and, —withdrawing said product stream from said reactor.

Abstract: According to one aspect of the invention, a method of converting an oxy halide salt into a halide dioxide in a reaction zone under certain conditions is provided. More specifically, the method includes generating chlorine dioxide from a stable composition comprising an oxy halide salt by introducing said composition to a reducing agent and minimum temperature within the reaction zone. According to another aspect of the invention, a composition for a stable chlorine dioxide precursor comprising an oxy halide salt is provided.

Abstract: The invention concerns a process for the production of chlorine dioxide comprising formation of chlorine dioxide in a reaction medium in at least one reaction vessel and withdrawing chlorine dioxide from said at least one reaction vessel, the process further comprising a step of treating reaction medium or at least one process stream originating directly or indirectly from said at least one reaction vessel with an adsorbent efficient for removing chlorinated organic compounds from said at least one process stream.

Abstract: The invention relates to a process for the production of chlorine dioxide comprising formation of an aqueous solution comprising chlorine dioxide, bringing at least part of the aqueous solution comprising chlorine dioxide to its end-application within an average residence time of less than 60 minutes, and maintaining part of the obtained aqueous solution comprising chlorine dioxide in at least one storage tank.

Abstract: The instant application provides apparatus and methods for the generation of gas, preferably chlorine dioxide. The methods and apparatus of the invention use a removable reaction chamber for the reaction of precursor chemicals, e.g., chlorite salt and an acid. The methods and compositions of the invention provide gas for a number of personal and commercial applications.

Abstract: Disclosed is a process for the production of chlorine dioxide, by which sulphuric acid can be efficiently mixed into the reaction mixture. The process apparatus includes a reaction vessel (1) operating in reduced pressure, in which alkali metal chlorate is reduced in acidic conditions. The reaction vessel (1) is equipped with a recirculation line (2) of the reaction mixture, including a circulation pump (3) and, downstream after the pump, a heat exchanger (4). The process is characterized in that the sulphuric acid is fed into the recirculation line (2) before the circulation pump, or into the circulation pump (3).

Abstract: According to one aspect of the invention, a method of converting an oxy halide salt into a halide dioxide in a reaction zone under certain conditions is provided. More specifically, the method includes generating chlorine dioxide from a stable composition comprising an oxy halide salt by introducing said composition to a reducing agent and minimum temperature within the reaction zone. According to another aspect of the invention, a composition for a stable chlorine dioxide precursor comprising an oxy halide salt is provided.

Abstract: Process for the continuous production of chlorine dioxide comprising generating chlorine dioxide in an aqueous reaction medium in a reaction vessel (1) maintained at sub-atmospheric pressure, bringing gaseous chlorine dioxide from said reaction vessel to an absorption tower (7) and contacting it therein with a flow of water to form an aqueous solution containing chlorine dioxide, bringing said aqueous solution containing chlorine dioxide to a stripper (12), blowing a gas through said aqueous solution of chlorine dioxide in the stripper to strip off from 10 to 100% of the chlorine dioxide entering the stripper and form a gaseous chlorine dioxide product.

Abstract: The invention concerns a process for the production of chlorine dioxide comprising generating chlorine dioxide in an aqueous reaction medium in a reaction vessel maintained at super-atmospheric pressure, withdrawing gaseous chlorine dioxide from said reaction medium, bringing withdrawn gaseous chlorine dioxide to an aqueous absorption medium and withdrawing gaseous chlorine dioxide from said absorption medium.

Abstract: The invention relates to a process for the production of chlorine dioxide comprising forming chlorine dioxide in a reaction medium in a reaction vessel and withdrawing chlorine dioxide as a gas from the reaction medium in the reaction vessel, the process further comprising adding chlorine dioxide to at least one raw material used in the process. The invention further relates to the use of chlorine dioxide for the reduction of the amount of chlorinated aromatic compounds occurring in a process for the production of chlorine dioxide.

Abstract: Steam stripper off gas from chemical pulp mills, for example kraft or sulphite pulp mills is rich in methanol and totally reduced sulphur (TRS) compounds. This gaseous stream is usually burned to avoid further handling of this TRS-rich, odorous stream. We found that once this gaseous stream is condensed, it can be used as a reducing agent in the chlorine dioxide generator, in place of purchased methanol. Surprisingly, we found that, in addition to the methanol component, the TRS components act as reducing agents during the production of chlorine dioxide or, at the very least, do not consume chlorine dioxide. The use of this stream in the ClO2 generator will allow pulp mills to reduce or eliminate the consumption of purchased methanol while providing a new approach to deal with TRS compounds in the chlorine dioxide generator rather than employing a dedicated TRS incinerator or any other combustion device.

Abstract: Chlorine dioxide (ClO2) is produced by apparatus and methods wherein a ClO2 gas produced in the apparatus is quickly introduced into a fluid stream to be treated with said gas. To this end, the apparatus has an interior chemical reaction chamber which houses an internal fluid flow tube having a fluid impervious upper section and a porous lower section that respectively define two zones within the interior chemical reaction chamber.

Abstract: The invention concerns a process for the production of chlorine dioxide comprising generating chlorine dioxide in an aqueous reaction medium in a reaction vessel maintained at super-atmospheric pressure, withdrawing gaseous chlorine dioxide from said reaction medium, bringing withdrawn gaseous chlorine dioxide to an aqueous absorption medium and withdrawing gaseous chlorine dioxide from said absorption medium.

Abstract: The invention relates to a continuous process for producing chlorine dioxide comprising the steps of continuously: a) feeding to a reactor (1) an acid, hydrogen peroxide and alkali metal chlorate; b) reacting the alkali metal chlorate with the acid and the hydrogen peroxide to form a product stream (2) containing chlorine dioxide, oxygen and alkali metal salt of the acid, c) bringing the product stream from the reactor to an eductor (3) and mixing it with motive water fed to the eductor and thereby forming a diluted product stream; d) removing oxygen from the diluted product stream; e) withdrawing part of the diluted product stream (9), before, during or after the step of removing oxygen; f) adding water (11) to the non-withdrawn part of the diluted product stream to form a recycle stream (12); and, g) bringing the recycle stream (12) to the eductor and feeding it thereto as motive water (4).

Abstract: The invention concerns a process for the production of chlorine dioxide comprising formation of chlorine dioxide in a reaction medium in at least one reaction vessel and withdrawing chlorine dioxide from said at least one reaction vessel, the process further comprising a step of treating reaction medium or at least one process stream originating directly or indirectly from said at least one reaction vessel with an adsorbent efficient for removing chlorinated organic compounds from said at least one process stream.

Abstract: A transportable gas sterilization unit having a chamber, a disposable gas generator utilizing chlorine dioxide as a sterilant, chemical quencher and a detector and a method of using the unit and to generate chlorine dioxide for medical instrument sterilization or disinfection. A two photon, photo-activated chlorine dioxide system and coatings utilizing chlorine dioxide as at least one sterilant material, and methods for coating medical instruments with the photo activated chlorine dioxide system.

Abstract: The halogen dioxide, chlorine dioxide is produced from its chlorite reactant using ion exchange media in a stable reactant form, and then passing a known concentration of counter ions through the ion exchange media in a moist environment so that there is an exchange of ions, and the reactants that are released form activated chlorine dioxide within the ion exchange material. The ion exchange media both contributes reactants to and extracts contaminants from the moist environment via its ion exchange mechanism. The counter ions may be derived from one or more stable precursor solutions which themselves may contain reactants and/or soluble catalysts. The reactants of the precursor solutions cannot act as the counter ion, or ions, in the ion exchange mechanism, but the soluble catalysts can. The ion exchange media can be mixed or layered with one or more insoluble catalysts, to enhance the formation of the activated halogen dioxide, chlorine dioxide within the ion exchange material.

Abstract: On-Line and Off-Line methods of simultaneously cleaning and disinfecting an industrial water system are described and claimed. The methods involve the addition to the water of the industrial water system of a Compound selected from the group consisting of the alkali salts of chlorite and chlorate and mixtures thereof; and an acid, followed by allowing the water in the industrial water system to circulate for several hours. The reaction of the alkali salts of chlorite and chlorate and acid produces chlorine dioxide in-situ in the water of the industrial water system. The chlorine dioxide kills microorganisms and the acid acts to remove deposits upon the water-contact surfaces of the equipment. An alternative method involves the use of a chelating agent and a biocide. Other possible cleaning and disinfection reagents may be added as needed including corrosion inhibitors, chelating agents, biocides, surfactants and reducing agents.

Abstract: Chlorous acid is generated from a chlorite salt precursor, a chlorate salt precursor, or a combination of both by ion exchange. The ion exchange material facilitates the generation of chlorous acid by simultaneously removing unwanted cations from solution and adding hydrogen ion to solution. Chlorine dioxide is generated in a controlled manner from chlorous acid by catalysis. Chlorine dioxide can be generated either subsequent to the generation of chlorous acid or simultaneously with the generation of chlorous acid. For catalysis of chlorous acid to chlorine dioxide, the chlorous acid may be generated by ion exchange or in a conventional manner. Ion exchange materials are also used to purify the chlorous acid and chlorine dioxide solutions, without causing degradation of said solutions, to exchange undesirable ions in the chlorous acid and chlorine dioxide solutions with desirable ions, such as stabilizing ions, and to adjust the pH of chlorous acid and chlorine dioxide solutions.

Abstract: The invention relates to a novel composition useful as a feed at production of chlorine dioxide, said composition being an aqueous solution comprising from about 1 to about 6.5 moles/liter of alkali metal chlorate, from about 1 to about 7 moles/liter of hydrogen peroxide and at least one of a protective colloid, a radical scavenger or a phosphonic acid based complexing agent, wherein the pH of the aqueous solution is from about 1 to about 4. The invention also concerns a process for producing chlorine dioxide using the novel composition.

Abstract: Chlorine dioxide generating processes of the single vessel type which produce chlorine dioxide of high purity are monitored and controlled by a computer using Advanced Control Strategies for steady, stable operation with optimum chemical usage on the basis of a desired chlorine dioxide production rate as the sole input from an operator to the computer program effecting the computer control.

Abstract: A method of producing chlorine dioxide (ClO2) is described which employs Urea as a reducing agent to reduce alkaline chlorate (NaClO3 or KClO3) in a mineral acid medium. The method of the invention can, for example, by means of a very high transfer rate, be used to reduce over 90% of the reactant, alkaline chlorate, to the product, chlorine dioxide. Furthermore, ClO2 product purity is accomplished, for example, over 95%. The mother solution of the reaction can then be processed, for example, to produce other useful inorganic salts, including potassium sulfate, potassium nitrate, sodium nitrate, and the like, and/or compound fertilizer resulting in useful chemical products rather than toxic waste. Accordingly, the method of the invention provides for efficient, cost effective, and safe production of ClO2 as well as inorganic salts and/or compound fertilizer.

Abstract: On-Line and Off-Line methods of simultaneously cleaning and disinfecting an industrial water system are described and claimed. The methods involve the addition to the water of the industrial water system of a Compound selected from the group consisting of the alkali salts of chlorite and chlorate and mixtures thereof; and an acid, followed by allowing the water in the industrial water system to circulate for several hours. The reaction of the alkali salts of chlorite and chlorate and acid produces chlorine dioxide in-situ in the water of the industrial water system. The chlorine dioxide kills microorganisms and the acid acts to remove deposits upon the water-contact surfaces of the equipment. An alternative method involves the use of a chelating agent and a biocide. Other possible cleaning and disinfection reagents may be added as needed including corrosion inhibitors, chelating agents, biocides, surfactants and reducing agents.

Abstract: The invention concerns a process and an apparatus for continuously producing chlorine dioxide, the process comprising the steps of feeding chlorate ions, acid and hydrogen peroxide as aqueous solutions to a reactor; reducing chlorate ions in the reactor to chlorine dioxide, thereby forming a product stream in the reactor containing chlorine dioxide; feeding motive water to an conductor comprising a nozzle; bringing the motive water to flow through the nozzle and causing it to flow further through the eductor in an at least partially spiral or helical manner, transferring the product stream from the reactor to the eductor and mixing it with the motive water and thereby forming a diluted aqueous solution containing chlorine dioxide, and; withdrawing the diluted aqueous solution containing chlorine dioxide from the eductor.

Abstract: The invention relates to a process for continuously producing chlorine dioxide comprising the steps of:

Abstract: Chlorine dioxide is produced at high efficiency in a continuous process effected using hydrogen peroxide as the reducing agent in a single vessel generator-evaporator-crystallizer at the boiling point of the reaction medium under sub-atmospheric pressure. The reaction medium is maintained under steady state continuous operation with a residual chlorine concentration while having no residual hydrogen peroxide concentration in the reaction medium.

Abstract: A method for producing chlorine dioxide by activating zeolite crystals (which have been impregnated with metal chlorite such as sodium chlorite, and optionally also a water-retaining substance such as magnesium sulfate, potassium chloride, potassium hydroxide, or calcium chloride) with excess protons, or activating an aqueous solution of metal chlorite and such a water-retaining substance with excess protons. Proton generating species useful for the activation are acids such as acetic, phosphoric, and citric acid, and metal salts such as ferric chloride, ferric sulfate, ZnSO4, ZnCl2, CoSO4, CoCl2, MnSO4, MnCl2, CuSO4, CuCl2, and MgSO4. The activation can be performed by causing fluid to flow through a bed of zeolite crystals impregnated with calcium chloride (or other water-retaining substance) and sodium chlorite, and a bed of zeolite crystals impregnated with a proton generating species. The two beds can be physically mixed together or the fluid can flow sequentially through separate beds.

Abstract: A method for producing chlorine dioxide by activating zeolite crystals (which have been impregnated with metal chlorite such as sodium chlorite, and optionally also a water-retaining substance such as magnesium sulfate, potassium chloride, potassium hydroxide, or calcium chloride) with excess protons, or activating an aqueous solution of metal chlorite and such a water-retaining substance with excess protons. Proton generating species useful for the activation are acids such as acetic, phosphoric, and citric acid, and metal salts such as ferric chloride, ferric sulfate, ZnSO4, ZnCl2, CoSO4, CoCl2, MnSO4, MnCl2, CuSO4, CuCl2, and MgSO4. The activation can be performed by causing fluid to flow through a bed of zeolite crystals impregnated with calcium chloride (or other water-retaining substance) and sodium chlorite, and a bed of zeolite crystals impregnated with a proton generating species. The two beds can be physically mixed together or the fluid can flow sequentially through separate beds.

Abstract: Gaseous mixture of chlorine dioxide and chlorine produced by reacting an inorganic acid with an aqueous solution of an alkali metal chlorate by controlled introduction of the inorganic acid into the aqueous solution of alkali metal chlorate. Inorganic acid passed through a volume of alkali metal chlorate flowing through a horizontal reactor in a plug flow regime results in an enhanced gaseous mixture of chlorine dioxide, chlorine and steam that can be withdrawn as a product stream.

Abstract: The invention relates to a process of producing chlorine dioxide comprising the steps of reducing chlorate ions in an acid reaction medium maintained in a reaction zone of a chlorine dioxide generator, which reaction medium contains alkali metal ions and sulfate ions, so to form chlorine dioxide and a solid salt of acidic alkali metal sulfate. The process further comprises the steps of separating said solid acidic alkali metal sulfate from the reaction medium, contacting said solid acidic alkali metal sulfate with an aqueous medium in a mixing tank to effect at least partial conversion to neutral solid alkali metal sulfate, separating the at least partially neutralized solid alkali metal sulfate from the aqueous medium on a rotary drum filter operating with vacuum inside and with part of the drum submerged in a slurry of the at least partially neutralized solid alkali metal sulfate and the aqueous medium, and forming an acid filtrate.

Abstract: Chlorine dioxide generating processes of the single vessel type which produce chlorine dioxide of high purity are monitored and controlled by a computer using Advanced Control Strategies for steady, stable operation with optimum chemical usage on the basis of a desired chlorine dioxide production rate as the sole input from an operator to the computer program effecting the computer control.

Abstract: The invention relates to method of producing chlorine dioxide comprising the steps of: providing a reactor with an aqueous acidic reaction medium containing chlorate ions; reacting said chlorate ions with hydrogen peroxide as a reducing agent in such proportions that chlorine dioxide is formed; withdrawing the chlorine dioxide from the reaction medium; wherein the content of tin in the reaction medium at steady state is maintained below 20 mg Sn per kg reaction medium.

Abstract: The invention relates to an aqueous composition of, up to about 90 wt %, hydrogen peroxide, comprising from about 0.05 to about 20 mmol/kg H2O2 of amino tri (methylenephosphonic acid), or salts or degradation products thereof, and a corrosion corrosion inhibitor, being either substantially free from or containing less than about 0.1 mole/l chlorate ions, having a tin content from 0 to about 100 mg/kg H2O2, and having a chloride content less than about 10 mg Cl−kg H2O2. The invention also relates to a process for producing chlorine dioxide where said composition is used as a feed.

Abstract: A solid-state chlorine dioxide generator for generating an aqueous solution of ClO2 is formed within a block comprising an eductor for establishing a vacuum pressure and a reaction column for producing ClO2 from precursor chemicals. The eductor has a water stream flowing therethrough which establishes a vacuum pressure and draws the ClO2 from the reaction column into the water stream to form an aqueous ClO2 solution. The reaction chamber comprises a novel transition zone of increasing flow area wherein the precursor chemicals thoroughly mix resulting in conversion efficiencies of precursors into ClO2 of 95% and above.

Abstract: A method for producing chlorine dioxide by activating zeolite crystals (which have been impregnated with metal chlorite such as sodium chlorite, and optionally also a water-retaining substance such as magnesium sulfate, potassium chloride, potassium hydroxide, or calcium chloride) with excess protons, or activating an aqueous solution of metal chlorite and such a water-retaining substance with excess protons. Proton generating species useful for the activation are acids such as acetic, phosphoric, and citric acid, and metal salts such as ferric chloride, ferric sulfate, ZnSO4, ZnCl2, CoSO4, CoCl2, MnSO4, MnCl2, CuSO4, CuCl2, and MgSO4. The activation can be performed by causing fluid to flow through a bed of zeolite crystals impregnated with calcium chloride (or other water-retaining substance) and sodium chlorite, and a bed of zeolite crystals impregnated with a proton generating species. The two beds can be physically mixed together or the fluid can flow sequentially through separate beds.

Abstract: A greater yield of chlorine dioxide from a chlorine dioxide generating process is obtained by providing acidic or acidity-generating components in the product chlorine dioxide solution to provide a chlorine dioxide solution having a pH below about 5.5.

Abstract: An aqueous solution of metal chlorate, mineral acid and a reducing agent are continuously or intermittently sprayed, in a pattern to achieve intimate mixing, into a spherical chamber creating an aqueous foam reaction mixture generating chlorine dioxide which is removed in a direction 90 degrees to the axis of the spray nozzles. A baffle plate may be used to reduce the open cross sectional area of the exit port to increase reaction efficiency. The reactants are a mineral acid and an alkali metal chlorate or chloric acid and a reducing agent such as hydrogen peroxide. The mineral acid is either diluted or concentrated sulfuric acid, hydrochloric acid, acetic acid, nitric acid or a blend thereof. The ratio of acid is greater than one and less than 3 kg acid per kg of ClO2 formed. The chlorine dioxide may be removed with a stripper column.