60results about "Chlorous acid" patented technology

This invention relates to a stable composition and method of making a thickened fluid composition comprising chlorine dioxide. The stable composition includes a mixture containing a chlorite, an acid source, and a thickener component. At least one of the chlorite, the acid source and the thickener component is in particulate form. In an embodiment, the mixture may be a unitary solid body wherein chlorine dioxide is generated upon interaction with an aqueous medium, such as water. A free halogen source may also be added to the mixture in some cases.

A massive body, e.g., a tablet, for producing a thickened solution of chlorine dioxide when the massive body is added to liquid water is disclosed. The massive body comprises a metal chlorite, an acid source and a thickener (incorporated directly into the massive body or added as a component separate from the massive body) and optionally a source of free halogen. The concentration of free chlorine in the solution will be: (a) less than the concentration of chlorine dioxide in said solution on a weight basis and the ratio of the concentration of chlorine dioxide to the sum of the concentrations of chlorine dioxide and chlorite anion in said solution is at least 0.25:1 by weight; or (b) equal to or greater than the concentration of chlorine dioxide in said solution on a weight basis and the ratio of the concentration of chlorine dioxide to the sum of the concentrations of chlorine dioxide and chlorite anion in said solution is at least 0.50:1 by weight.

A massive body, e.g., a tablet, for producing a solution of chlorine dioxide when the massive body is added to liquid water. The massive body comprises a metal chlorite such as sodium chlorite, an acid source such as sodium bisulfate and a source of free halogen such as the sodium salt of dichloroisocyanuric acid or a hydrate thereof. The concentration of free halogen in the solution will be:

• • (a) less than the concentration of chlorine dioxide in said solution on a weight basis and the ratio of the concentration of chlorine dioxide to the sum of the concentrations of chlorine dioxide and chlorite anion in said solution is at least 0.25:1 by weight; or
  • (b) equal to or greater than the concentration of chlorine dioxide in said solution on a weight basis and the ratio of the concentration of chlorine dioxide to the sum of the concentrations of chlorine dioxide and chlorite anion in said solution is at least 0.50:1 by weight.

A composition for the generation of chlorine dioxide including at least one non-iodo interhalide, polyhalide or salt thereof having the formula

Br_mCl_nF_oX_p

wherein m=0–3, n=0–4, o=0–3, p=0–2, X is a cationic moiety and with the provisos that m+n+o cannot be zero; if m+n+p<2, or mixtures thereof, and at least one source of chlorite ions.

The present invention is directed to both physical and chemical means for maintaining continuous high levels of chlorine dioxide in aqueous solutions for extended periods, with minimum loss through degradation in the solution and dissipation through the walls of the containing vessel within which the solution is stored. The ClO2 may be maintained even in the absence of very high levels of chlorite, from which supplemental, offsetting levels of ClO2 may be generated. The present invention relates to the discovery that certain types of plastic and glass containers have the ability to maintain relatively constant levels of ClO2 in their contained solutions over extended periods, particularly in aqueous compositions comprising chlorite/ClO2 ratios sufficient for a stabilizing complex of the two, presumably Cl204-, to suppress the ClO2 loss. Of particular value is certain high-density polyethylene terephthalate (PETE) plastic bottling and plastic containers which have been initially exposed to a fluorinating environment. Specifically, in the latter regard, it has been discovered that certain plastic containers which ordinarily are incapable of maintaining aqueous ClO2 levels can be treated with fluorine gas to transform their surfaces so as to effectively suppress ClO2 diffusion therethrough.

A two-part disinfecting systems, as well as disinfecting compositions and methods for making and using the same. The two-part disinfecting system contains a first part and a second part adapted to be mixed to yield an aqueous disinfecting composition, wherein the first part comprises a chlorite and the second part comprises an acid, and wherein the first part, the second part, or both the first and second parts comprise an olefin compound.

Described herein are chlorite formulations having a pH between about 7 and about 8.5, wherein the chlorite formulations are substantially free of deleterious non-chlorite components. Described herein are chlorite formulations, including pharmaceutical formulations, which are formulated for systemic, parenteral, or intravenous administration. Described herein are methods of preparing and methods of using the chlorite formulations described herein.

A dry disinfectant composition for the production of aqueous solutions of chlorine dioxide of predetermined concentration is formulated of a mixture of lithium hypochlorite, sodium bisulfate and sodium chlorite. Special liquid and dry formulations are also contemplated for convenience of use, for quality assurance and for safety.

This invention comprises a lightweight, portable chemical combination of reagents for sterilizing or disinfecting objects in the absence of electrical power or fire. The chemical combination includes a chemical oxidant with the capacity to liberate a biocidal intermediate, a chemical reductant of the oxidant with the capacity to react with the oxidant, and an effector to induce a reaction between the oxidant and reductant. In one embodiment, the oxidant comprises chlorite, the reductant comprises sulfite, and the effector comprises ascorbate. In another embodiment, the chemical combination comprises the oxidant, reductant, effector and iron-activated magnesium. When water or water solutions are added to either embodiment, the chemical combination generates heat, steam and a biocidal intermediate that can destroy contaminating microorganisms. In one embodiment, the biocidal intermediate is a halogen-based biocidal intermediate, such as chlorine dioxide. In another embodiment, the biocidal intermediate is a halogen-free biocidal intermediate.

The present invention is generally directed to a method of producing an aqueous solution of chlorine dioxide from the reaction of a metal chlorite and an acid forming component which do not react to produce chlorine dioxide in the substantial absence of water. The reactants are separated from liquid water by a membrane which allows the controlled passage of liquid water and/or water vapor into contact with the reactants. The chlorine dioxide thus generated passes out through the membrane into the liquid water to produce the desired aqueous solution. Aqueous solutions containing chlorine dioxide produced in this manner can be conveniently used for commercial and domestic cleaning operations such as in the food industry.

The description relates to a process for the production of aqueous chlorine dioxide solutions through oxidation of chlorite with oxo acids and/or oxo acid anions having a suitable redox potential in a buffered aqueous medium, wherein an acidic aqueous solution A is produced which has a pH of about 5 or less and contains the oxo acids and/or oxo acid anions, and the acidic aqueous solution A is mixed with an aqueous chlorite solution B to form chlorine dioxide, wherein a pH of less than 6.95 is adjusted in the reaction mixture, this pH value being stabilized by a buffering system contained therein.

Alkali metal chlorite, particularly sodium chlorite, is produced with a level of purity superior to that expected based on the composition of the chlorine dioxide generator off-gas that is used as a raw chemical feed for chlorite manufacture. The off-gas is preferably drawn before it enters the chlorine dioxide absorption tower and is passed through a conditioning stage to then react in a liquid medium to produce an alkali metal chlorite solution from which the unreacted and produced gases are immediately separated.

A process for preparing sodium chlorite includes such steps as dissolving hydrogen peroxide and solid sodium chlorate in water, adding the resultant solution along with sulfuric acid to a ClO2 generator to generate the mixture of ClO2 and oxygen, loading the mixed absorbing liquid containing sodium hydroxide and hydrogen peroxide into an absorbing tower, adding ClO2 to the absorbing tower while escaping oxygen, and finally generating sodium chlorite. Its advantages are high output rate (more than 95%) and high purity (more than 95%) of product.

The invention discloses a method for preparing sodium chlorite through a comprehensive method chlorine dioxide process. According to the reaction principle, the method includes the steps of firstly, conducting sodium chlorate electrolysis according to the chemical equation NaCl+3H2O->NaClO3+3H2; secondly, conducting hydrochloric acid synthesis according to the chemical equation H2+Cl2->2HCl; thirdly, generating chlorine dioxide according to the chemical equation NaClO3+2HCl->NaCl+ClO2+1/2Cl2+H2O; fourthly, preparing sodium chlorite according to the chemical equation 2ClO2+2NaOH+H2O2->2NaClO2+2H2O+O2. A preparation device mainly comprises an electrolytic cell, a sodium chlorate reactor, a hydrochloric acid synthesis furnace, a reboiler, a chlorine dioxide generator, a chlorine dioxide absorption stripping tower, a chlorine dioxide stripper and a sodium chlorite preparation tower. When sodium chlorite is prepared through the method and the device, the product cost is low, yield is high, no side products are discharged, no waste acid or solid waste is discharged, environment pollution is reduced, and the advantages of being economical and environmentally friendly are achieved.

Alkali metal chlorite, particularly sodium chlorite, is produced with a low carbonate level by combining a chlorine dioxide generating system operating at subatmospheric pressure with a chlorite formation reactor in which the chlorine dioxide reacts with hydrogen peroxide in the presence of aqueous alkali metal hydroxide, particularly sodium hydroxide.

This invention relates to a method for enhanced sanitation and oxidation of aqueous solutions at aquatic facilities. The method provides a means for the in-situ generation of chlorine dioxide from dilute solutions of chlorite anions at near neutral pH, and enhanced inactivation rates of microbiological organisms including cryptosporidium.

The invention discloses a preparation method of sodium chlorite. The preparation method comprises the following steps of (1) enabling sodium chlorate solution to react with hydrochloric acid to generate chlorine dioxide gas and chlorine; (2) leading chlorine dioxide gas and chlorine into sodium chlorite solution to further react, so as to generate chlorine dioxide gas; (3) leading the chlorine dioxide gas into sodium hydroxide solution, and adding hydrogen peroxide to react, so as to generate sodium chlorite at the same time; (4) crystallizing and drying sodium chlorite prepared in the step (3) to obtain a final product, wherein the concentration of the sodium chlorate solution in the step (1) is 25-33%, the concentration of hydrochloric acid solution in the step (1) is 31%, and the molar ratio of the hydrochloric acid to chlorous acid in the step (1) is (1-1.5) to 2. The preparation method of sodium chlorite disclosed by the invention does not utilize concentrated sulfuric acid of which the concentration is over 95%, is easy in control of the reaction process, not drastic in reaction, higher in safety coefficient, low in cost, and suitable for industrial large-scale application at the same time.

The creation of chlorine dioxide in a water system can be accomplished by an improved mixture of components that includes a chlorite salt, oxidizing chlorine releasing agent(s) and an acid source and these improved combinations of materials can be pre-measured and delivered into a water system in sealed water soluble containers.

A composition for generating chlorine dioxide comprises active ingredients, a suitable hydrophobic compound, and a suitable super absorbent compound. A suitable hydrophobic compound will, among other characteristics, repel the solvent for at least the initial 30 seconds of exposure thereto. A suitable super absorbent compound will, among other characteristics, absorb at least 75 times its weight in solvent and will not gel until the chlorine-dioxide generating reaction is substantially complete.

The invention discloses a method for preparing high-purity chlorine dioxide and sodium chlorite by a ferrous sulfate method. The method comprises the following steps of: crushing ferrous sulfide; dissolving sodium chlorate into water to obtain sodium chlorate solution; diluting concentrated sulfuric acid by adding water, adding the diluted sulfuric acid into the sodium chlorate solution and uniformly mixing the solution; adding the mixed solution into ferrous sulfide powder; performing reduction reaction when stirring to produce high-purity chlorine dioxide gas; and inputting the gas into mixed absorption liquid consisting of hydrogen peroxide and sodium hydroxide, and thus obtaining the high-purity sodium chlorite solution, wherein the purity of the high-purity sodium chlorite solution is larger than 98 percent. According to the method, due to the adoption of the ferrous sulfide, the chlorine dioxide is obtained by the one-step reaction, and the sodium chlorite can be obtained by the two-step reaction; the conversion rate is up to more than 97 percent, the purity of the obtained chlorine dioxide and sodium chlorite is high, and the method has a simple production process and low cost, and is easy to industrialize.

A method for determining the concentration of chlorine dioxide in a chlorine dioxide solution having the following steps:

(1) isolating two samples, Sample 1 and Sample 2, from the chlorine dioxide solution;

(2) stripping the chlorine dioxide from Sample 1;

(3) completely converting the chlorine dioxide in Sample 2 to other chlorine species;

(4) transporting the chlorine dioxide samples either within the facility or outside the facility to a testing site;

(5) separately determining the concentration of the chlorine containing species in each of Samples 1 and 2; and

(6) calculating the concentration of chlorine dioxide in said chlorine dioxide solution based upon the information obtained in step (5).